This is where you end up when you read too much on the CG website... ;-) The E-61 is a great technology that is over 40 years old, but still very relevant. Superlative espresso that will rival 99% of the coffee shops where you live (unless it's Vancouver or Seattle...)
Negative Product Points
No easy direct-plumb option. Sensitive to power surges (even slight ones). Hot grouphead will scar you if you aren't careful. Long cooling flush.
I've been on coffeegeek for over a year now. I don't know how it happened, but I turned around and all of a sudden I've contracted an incurable illness! ;-)
I started off with a gaggia coffee, which is a great machine, but after determining that this was more than a passing obsession, I yearned for more. After endless research, I decided on this machine. I bought it used from a fellow cg'er. I looked at the Oscar, Anita, Zafirro, etc, before deciding on this machine. I chose this one because it was second-hand priced, and highly respected by David Schomer. The Oscar was a no go due to lack of a hot water tap. The anita would have been right there, but I didn't want to spend the extra $.
When I first got the machine, I was having trouble. The water was not hot enough through the grouphead. I eventaully tracked it down to excessive loose scale insulating the HX from the boiler heat. Repeated backflushing and thorough cleaning solved this problem. The next problem was the controller getting fried. After lots of help from 1st-Line, I got the replacement part and all was good. They thought it was due to a power surge from a thunderstorm, so now I have a surge protector on that outlet.
If you are going to do any milk drinks (and you often will if you have friends), then I would highly recommend an E-61 or dual boiler. Single boiler units like the zafirro are easier to use for espresso only, but will shortly be frustrating if you steam milk at all. You also have to learn the cooling flush thoroughly described on home-barista.com in Dan Kehn's article: http://www.home-barista.com/hx-love.html The water coming out of the grouphead when you first pull the lever is over 212'! Waaaay to hot for espresso.
It's amazing that this technology is over 40 years old, but still very capable. The next step up would have to be substantial, such as the LM GS3 or a dual boiler machine, and I don't think it's going to be much better espresso, mostly ease of use (like less cooling flush, simultaneous frothing / brewing). This machine is easily capable of top-notch quality espresso. All these machines with e-61 groups are going to be similar in terms of quality / use.
I bought it used, so no vendor used.. but 1st-Line was very helpful for me when I had troubles.
Three Month Followup
After living with this machine for a while, probing the temperature by hand was getting to be a hassle... enter the Eric S. thermocouple adapter:
I would say this is an essential purchase for use with an e61 machine. No, really - go buy one now. If you want to easily make consistently marvelous espresso - it'll make life very simple for you!
I would only add that I'm not too happy with reliability on some of the machine's components. The controller has gone out twice, and it was a bit of a job rewiring from the old giemme to the new gicar box - but I posted my results here and on home-barista. I think I'm just unlucky with that though, as others have not had the same problems. I also repaced the pstat with the Jaeger unit from Chris' coffee, and it seems to be holding up much better than the ceme pstat it comes with (so far, knock on wood...).