A terrific machine if you can afford it, and you have the space on your counter for it.
Positive Product Points
Very easy to use, stable brew temperatures, powerful steaming, can be plumbed in or run off the internal tank, quiet rotary pump
Negative Product Points
Expensive, fairly bulky on the counter, some of the fit and finish could be better, not much clearance between the spouts and the drip tray.
I've had the Alex Duetto II for almost a year now, and it's been a joy to own. It has a PID controlled dual boiler design, so you don't have to worry about pulling your shots at the wrong temperature once you have the PID dialed in. Just a quick warming flush, then pull your shot. So easy a cave man could do it. The legendary e-61 group also makes pulling shots really easy, since the preinfusion and water flow from the group is very forgiving. Of course, you still need a good grinder and fresh beans, but that's true of any machine.
The steam boiler provides ample steam, even when set to 15 amp mode like mine. Go for 20 amp mode if you have the wiring for it, and you will get faster recovery times and even better steaming, but it's not really necessary for average home use. The stock no-burn wands are a nice touch, but I prefer the microfoam from standard "burn me" wands, so I switched back to an uninsulated steam wand soon after buying.
Having the ability to plumb in or run from the internal tank is really nice. At first I ran mine off the tank, but after a week or two I plumbed in, which is much more convenient since you never need to worry about running out of water in the middle of a shot. You will need to buy a filter and softener from Chris, as well as John Guest tubing and fittings to connect the machine to your water supply. Plumbing in to my water pipes was a pain, but that was because I have an older home with weird plumbing, not because of any problems with the machine. Most houses should allow easy plumb in.
My only nitpicks are pretty minor. There are some sharp edges to the drip tray cover and some of the stainless steel frame parts, so be careful if you have to reach inside the machine. Also, the drip tray is fairly tall because of the water plumb in switch underneath it, so there isn't much clearance between the spouts and the drip tray to fit cups. My 6 ounce cappuccino cups barely fit underneath. Using a naked portafilter helps. The drip tray also tends to overfill and leak a bit if you don't empty it often, since there's notch cut out of the back of the tray to fit the discharge pipe for the vacuum breaker valve. No big deal, but it would be nice if it didn't drip at all.
Other than those minor niggles, the machine has been running trouble free for almost a year now. It's so easy and fast to use that it allows me to just relax and enjoy the excellent espresso. Having pinpoint control over temperature also brings out flavors that I missed on my old HX machine, which I always thought was very good.
Excellent. Chris' Coffee is the best in the business, with excellent customer service both during the purchase process and even years after you buy from them. Why go anywhere else?