When I bought QM's Andreja Premium (in Europe, through Chris Coffee, named after owner Chris Nachtrieb) almost five years ago, the main alternative was a simple single boiler VBM (Vibiemme).
I would call these machines you want to compare "single-boiler-HX" or just "HX" with "E/61" group - a level up from the home standard 5 years ago.
Today, you might say through Chris' work, the industry has many competing designs in this class.
At the time, dual boiler was not an option in the semi-pro or higher-end home market.
Today, would I make the same choice?
I am not 100% sure about that, but it is likely. I now know I would spend more money on a grinder, still, than the coffee machine.
I don't do any milk based drinks at all - just double espressos.
Would I need the HX with steam? Well, that is what the "E/61" group was designed for.
The group overheats a little during idle, so a cooling flushing is needed, but a single boiler (no HX) likely needs to be flushed to raise group temperature a little after idle. And the dual boiler would behave the same like the single without HX.
In this respect, a multi-group machine (2 or 3) provides escapes for moving to a different group that is not too cold, but still needs to have a little flush before operating it. Even larger machines (4 or 5) would allow more parallel use of groups. This implies there are physical limitations to the number of coffees these machines can do in series on a single group - here I suspect the HX design is superior to the other ones.

I prefer Andreja's cabinet design over the plain boxy shape of competition.
Andreja Premium actually switches the heating element with a solid state relay, which in turn is switched by the pressurestat. The Sirai "commercial" of great fame is unnecessary because of this. The standard CIEME pressurestat is used by La Marzocco as well and has, narrow, adjustable even, hysteresis (however I replaced that one by the Jaeger from Chris Coffee).
Also Andreja Premium has these excellent valves (faucets) and no-burn tubes.
It can be plumbed, but this requires some internal work. Emptying the drain tray is always a manual thing and when plumbed in, this will need to be done frequently. The latter because of pressure regulation: the pump produces more pressure than required and a regulation valve offers adjusted pressure to the group whilst some (heated) water flows back into the water tank; however when plumed in that over-pressure water is fed into the drain tray.
The vibration pump can get noisy, however I accept that. It is a matter of routing the silicon tubes, the wiring harness and the copper tubes to manometers so as not to conduce or pick up pump vibration. If you "get it", the machine can be dead quiet, really. I just did not have the incentive to work on it.
My Andreja Premium is on a clock and "on" 16 hours daily.
Maintenance I had, was replacement of the vacuum release valve (a simple part of which actually only the tiny O-ring needed replacement), the seals/gaskets of the lever to the three way valve (and pump on/off switch), and the valve gaskets inside the E/61.
Water I use is from RO (reversed osmosis) which could lead to some build up of metal-oxides from the inside of the machine, however there is no calcium in the water. Using pour-over, the RO water prevents build up of any dirt or biofilm in the water tank. Also, I do not worry about the fresh water to become warm.
I would expect some issue with the level sensor or level measurement due to the RO water, but did not notice any. I might need to repair either level sensor or control box in the near future, though - aging, I guess.

Looking at the Izzo Alex, the same price, I would say its execution is less in a few ways and maybe superior in a few other. Less are the valves (faucets) of hot water and steam, as well as the tubes from these. To me these are important, but this is personal.
Also, the level detection in the fresh water tank is inferior (spring loaded under the tank and based on weight in Izzo Alex, whereas Andreja Premium uses a floating magnet in the tank and magnetic switch outside the tank).
As implied above, I prefer the design and think it has better WAF (wife-acceptance factor) consequently.
Izzo Alex may be superior in plumbing in.

As to ability of each machine to deliver excellent coffee - which is what this is all about - I do not believe the two have big or significant differences. Steaming may differ, but I would not steam and do not know it.

Yesterday I had a ristretto in a restaurant in Amsterdam (Netherlands, Europe) from a Nestlé (black) cup or pod and a sophisticated professional machine. Bad, really bad. The best this coffee can score is 7 out of 10, but here the score was 4. So, later, when I walked by a fancy coffee (bean) outlet that serves their coffee from a Kees van der Westen Idrocompresso Tripletto, I felt I should ask what blend was in the grinder today. "Sicilian" - does that mean a very dark roast, I asked? OK, give me an espresso. They had totally missed the point in the preparation; score 5 out of 10. Too much acidity and no proof of the dark roast.
"Let's go home to have coffee," my wife said, "as your coffee is infinitely better."

As the Italians say it is about the 4 M's (machine, grinder, hand, coffee blend) - or was there a 5th M in Italian, even?
Use serious money to spend on kilograms of coffee and your learning process - accept sink shots and just dump those in there. If you don't, it can take years to improve. And you need to develop your nose and taste buds, and preferences.

The two machines compared here, are from the same distributor that I have positive experience with, even though he is in the US and I am Europe based.

On general points this is an even match. Personal preference at and until this price point: Andreja Premium for unplumbed pour-over water tank machines.
Spend significant money on the grinder. Buy a digital cooking thermometer. Hold it into the spout of the portafilter and flush until your desired temperature.
Grind fluffiness, distribution and leveling are important.
Tamper is a matter of fit, taste and ergonomics.
Spend serious time and money on coffee.

Would I want improvements still? For starters the plastic insulation shoes over the electrical connectors in the wiring harness really become brittle too soon (by exposure to heat). If I built the machine myself, I might put in a second, cheaper, pump to fill the boiler and separate tubing and electric circuit for this function. Also, I would have an additional switch in the heater circuit for keeping the heater off during the filling of an empty boiler. I gave PID much thought and must admit it seems appealing, but am not sure of its influence on the learning process of the hand and taste of the barista. Anyhow, all "improvements" come at a cost and do not necessarily improve the taste of the coffee.
I did replace the standard portafilter for a La Marzocco, but found the original filter/basket superior over LM's.
LM's PF is heavier (more brass) and slightly different in headroom (needs a thicker, higher gasket).
A grinder upgrade will change the entire experience, I expect.

Oh, and did I mention the coffee?

Regards
Peter

Thanks for all the great advice. Now....to actually make a decision is not in my nature.

Take a trip to Chris's Coffee with a check in your pocket. Try out a couple of your favorites and come home with it knowing that's it's going to be a very Merry Christmas.

Mark

akallio wrote:Well, I did not. I guess they could have placed it under the water tank if they really wanted to.

True, but it appears doing so would require a tank re-design, possibly ending up with a smaller one than what is currently used, even if both the Gicar and pump were relocated under the water tank. Having said that, I would prefer an under water tank arrangement as it would prevent the pump from leaking water into the motor when it does give up the ghost. But in all honesty, given the reliability of rotary's, it should be quite some time before this issue arises.

Photo courtesy of Chris Coffee

On a side note, are the brew boilers really non-insulated as seen in this picture? Seems like, although water temp in a brew boiler is just above 220 versus the 270 - 290 in a steam boiler, it should be insulated to protect the electronics that are in close proximity from getting overheated. Anyone mount a thermocouple in there to measure the temp? More importantly, is this a legitimate concern, or are the electrical components located in close proximity just junction boxes?

Photo courtesy of Chris Coffee

On a side note, are the brew boilers really non-insulated as seen in this picture? Seems like, although water temp in a brew boiler is just above 220 versus the 270 - 290 in a steam boiler, it should be insulated to protect the electronics that are in close proximity from getting overheated. Anyone mount a thermocouple in there to measure the temp? More importantly, is this a legitimate concern, or are the electrical components located in close proximity just junction boxes?

They are non-insulated in the first models. I've understood that steam boiler is insulated in newer models and many people have insulated it by themselves. I have not bothered, because I keep the boiler off almost all the time. Insulating brew boiler would not be useful and harms temperature stability.

Earlier Alex models did not have big problems with overheating except for the Gicar box. Now it is located in a better place, next to tank and behind a separating wall. Of course the new PID controller is close to boilers and it remains to be seen how well it fares in the long run.

uscfroadie wrote:Having said that, I would prefer an under water tank arrangement as it would prevent the pump from leaking water into the motor when it does give up the ghost. But in all honesty, given the reliability of rotary's, it should be quite some time before this issue arises.

Seems that if it fits into the case with the pump mounted on top that a couple of brackets and a couple of longer braided hoses would let one mount the pump/motor with the pump on the bottom. But if that rear bearing fails odds are you still would have some water damage, though no where near what would happen with water draining over the motor.

-Cecil

I spoke to Chris at length and he was incredibly helpful. I agree with all the great posts about him. I think I'm going to run up and see the machines before I buy though. Now I'm leaning towards the Mini V....

I'm a similar situation but considering a different consideration set: the Quick Mill Vetrano and the Rocket Giotto Professional. I imagine that at this price point, both should be very good machines and should produce similar shots. Both seem to have the same general internals (Sirai p-stat--$59 option on QM, rotary pump, high end value/knobs, two pressure gauges). The difference seems to boil down to three things: Price (Giotto is $200 or so more expense), Aesthetics and WAF (Giotto is much better looking) and future Service (Chris Coffee for the Vetrano vs. Seattle Coffee or SweetMarias for Giotto).

Am I missing anything?

thomgonzales wrote:I'm a similar situation but considering a different consideration set: the Quick Mill Vetrano and the Rocket Giotto Professional. I imagine that at this price point, both should be very good machines and should produce similar shots. Both seem to have the same general internals (Sirai p-stat--$59 option on QM, rotary pump, high end value/knobs, two pressure gauges). The difference seems to boil down to three things: Price (Giotto is $200 or so more expense), Aesthetics and WAF (Giotto is much better looking) and future Service (Chris Coffee for the Vetrano vs. Seattle Coffee or SweetMarias for Giotto).

Am I missing anything?

The Vetrano w/ the Sirai upgrade is $1654, whereas the Giotto w/ rotary pump is $1999, so it's roughly a $350 difference. Both should be equipped with an EricS grouphead thermometer, and both are fine machines. If the sheetmetal on the Giotto is $350 more appealing to you, I say go for it. If not, get the Vetrano. Either way you'll be thrilled with your purchase.

I'm not sure why you guys want to upgrade to the Sirai.
Yes, it is big, HUGE.
Why? Because it should be able to switch loads of Amps.
Is it better than a small CEME or Jaeger?
Define better.
Precision and width of hysteresis, I would say.
Having read all sorts of debates on the Sirai, I got the impression it really is not better at these values, except maybe the switching of loads of Amps.
(BTW, in Europe at 230V, the Amps are half the issue.)

In the QM, Chris, or QM themselves, integrated a Solid State relay (SSR) that switches the Amps of the heating element and the SSR is switched by the pressurestat (CEME or Jaeger).

Why bother?

Regards
Peter