I'm embarrassed to admit that I own this grinder, but I bought it on impulse because I'm a sucker for vertical mounted burrs. My theory (entirely not borne out yet) is that there should be less grind retention, less clean up and fluffier grounds since they go right into the porta filter. Also, because of the auger, there is almost no popcorning.
I don't use the hoppers, but they are good and have sliding cut offs so you can use one side at a time -- though if you forget to turn off the other side, you'd go through a pound of coffee in a few seconds! (Which is why I don't use them.)
I also thought that two heads would provide me with a drip and an espresso side.
The grinder is made in France. Burrs are still available from Santos at $132/set (I found out after the fact). The grinder came with a couple extra new burr sets, but these only fit on the "front" side which rotates to the left. The back side (the one without the base sticking out) rotates to the right. Those burrs were shot, and rather than ordering a new set with a 3 month wait, I took a chance and ordered a pair of Fiorenzato T80 63x38x9.5mm DX from Stefano at $43. I figured I'd have to modify something.
The coffee gods gave me a break; they fit perfectly and seem to work fine, though I am far from even beginning testing. So, if you're stuck with a Santos with a right hand rotation, burrs can be bought quickly and reasonably. I haven't looked into replacing the left hand set since with two new sets, I doubt I'll have to worry about it anytime soon.
As to the grinder itself, I'll get around to doing some tests at some point. It works well for drip; I've been doing that for a few months and it grinds 50 grams in less than five seconds. It isn't very loud (much quieter than my old Rossi).
For espresso, it is more problematic. It is easy to make it stepless -- the removal of a ball bearing detent takes just a couple minutes. However, the range of useful adjustment for espresso is about 1.25 inches; in other words, you don't have too much fine tuning range. It will go much finer than espresso, easily Turkish, so espresso is not pushing the burrs to the end of their range (as is the case with using my hand grinder, Spong). That is actually quite important. Also on the plus side, going from espresso to drip takes a split second adjustment (while the grinder is on) which is really nice compared to other grinders.
I found myself dealing with this issue by usually keeping it at one setting and adjusting the dose. So, for example, if 15 grams gave me a shot at 20 seconds, a half gram adjustment (making it 15.5 grams) would bring it in at 25-27 seconds.
But trying to adjust it by using the knob for fine adjustments isn't that practical.
As far as taste goes, I don't have enough experience with the grinder, other grinders and the new MCAL to make any conclusions. I can say that the espresso is certainly at the Blue Bottle level, at least, though due to the MCAL (I guess), not as full bodied. The La Peppina (before I sold it) gave fuller shots.
I'll do some retention tests and continue to use the grinder until I finish making my own -- I have not given up on that project -- but having a working grinder seems to put it on the back burner to some degree. Sometime I'd like to get together with someone with a Mazzer or K.x and compare shots -- that would be very helpful.
************************* UPDATE **********************************
It's been a few months and the grinder is growing on me. I really like the straight bean path. The espresso grind is totally and consistently clump-less. It is one of the uglier, faster and easy-to-clean grinders. I still haven't A-B'd it against a Titan, but sometime I will. It is not micrometer adjustable, but I haven't found that to be a problem since I began using a scale to dose. I adjust to close with the grinder and fine tune with the dose. There isn't any caked up coffee inside after months of use, but there were a 3-4 whole or half beans in the back of the chamber. That probably can be fixed easily, though I'm not motivated to do so right now.
I decided to reduce its stature a bit to fit under the counter. This involved taking the machine apart, sawing the sides down, shortening and re-threading some bolts, rewiring the switch and making holes for the relocated switch and power cord. It took about 3 hours. The only interesting thing about the job was my first use of a newish sort of steel cutting blade that can be used in a wood chop saw. The blade cut through the sheet steel like it was nothing -- few sparks, not a lot of noise and very clean, milled cut. Really amazing.
AFTER THE CUT
MOTOR WITH HOPPER REMOVED
I continue to use the grinder, mostly for drip. It continues to do a good job. I use the other side of the machine to grind dry mushrooms into powder and it works quite well for that.