So I've sorted out the steaming. And I've gathered input from experts.
And I was to the point where the only real issue I had was with the stock baskets (using the Linea Espresso) so I figured it was time to roll in some new coffees.
First, I switched over to the Stumptown Hairbender for a few days. I figured this would be a real test, as the Hairbender is notoriously challenging to work with. In addition, it's a complex, multi-bean blend that tends to benefit from updosing and under-extraction - so I knew this would be a good test of the stock baskets.
I pulled shots using the stock 21g basket (based on Strada-derived feedback from friends at Stumptown) as well as from the Simonelli basket - and from my GS (using the Simonelli basket) as a frame of reference.
The difference between the shot on the GS (with the Simonelli) and the shot on the Mini (with the same basket) was small and subtle. The shot from the Mini was "fluffier" and had lower "density" on the palate. The aftertaste didn't last as long. Otherwise, very comparable.
That's just nuts
. In general, I shy away from working with the Hairbender on home machines. One of the great glories of the initial prototype GS/3 was how I was able to get good shots of this espresso using it. I was simply unused to a standard home machine being able to cope with the requirements of this coffee.
In addition, my GS is in many ways ideal for the Hairbender. I've kind of calibrated that machine for the Hairbender at this point.
So to be able to pull shots of Hairbender from this 110v home machine that are comparable to what I get off a completely dialed in, 230v commercial machine... that's just... well... it's insane. Seriously. This machine is nuts.
When I switched to the stock 21g basket, on the other hand, things got weird. I was able to get consistent shots after I'd got the grind right. It was relatively easy to work with once dialed in as well (especially using the Anfim). But the flavor in the cup was dominated by Indonesian coffee notes, with a lot of mushroom funk that wasn't even identifiable in the other shots using other baskets. In addition, there was a decrease in viscosity and most of the cherry flavor vanished. Finally, I actually ended up having to run at a higher brew temp using this stock basket.
No matter what I did, I was unable to get a shot from the stock basket (even with guidance from Stumptown) that was comparable to what I was getting from the after-market baskets. And I burned through all my Hairbender trying to do so.
OK, so that's a three bean blend and a five bean blend. The first of them is optimal in my experience with a slight updose and slight under-extraction, and the second seems to shine most at very heavy doses and rather heavy under-extraction. So for my next coffee I decided to choose a Single Origin Espresso (in this case, the Linea Caffe Brazil FAF) - which is lighter roasted and optimal at a neutral dose and full extraction.
This was clearly the type of coffee that the stock baskets were intended for. With this coffee, dialing in the shot was super easy. Getting optimal tasting shots was quick, and once I had the grind, dose and temp correct the shots were incredibly
I'm going to predict that working with a lighter roast single origin espresso is going to be nearly brain-dead easy (especially if you either weigh each shot or are an experienced barista using a timed grinder like the Anfim).
Compared to shots from either the EPNW basket or the Simonelli one, with this coffee the shots from the stock basket had far greater transparency and clarity. Sweetness was improved and the shots had wonderful sparkling acidity. In addition, I was able to get far more complete extraction without losing body or developing astringent flavors.
I'm going to suggest that anyone buying this machine should probably augment the stock baskets with an aftermarket basket that is optimized for complicated blends and/or coffees that are best when dosed outside the designed "neutral" band for these baskets. If I owned this machine, I'd have three baskets on my machine: the stock 17g, the stock 21g and the EPNW Precision or Simonelli double.
The stock baskets really require a fine grind / neutral dose / full extraction approach to the coffee. When measuring your coffee, this results in a relatively idiot proof way to get consistent and acceptable extraction from most coffees. If you want to go with a different approach or you want to do fine-granularity tweaking of the parameters, you're probably going to want to at least experiment with different baskets.
Now... after-market baskets are probably the cheapest "upgrade" you could have to face with a new machine. So this isn't that painful. And with that additional basket (and in my case a different portafilter) I think this machine would be absolutely perfect
for my home needs.