Now that the pricing is out on the Alpa FPS, it's interesting to compare the two.
I have an HCam-B1 in Canon mount, and one advantage the HCam has over the FPS is its sliding back. For a fairer comparison, it probably makes sense to look at the HCam-B1i, which has a fixed back.
The B1i including the digital back adapter is $6839 at current exchange rates.
FPS is $8335, but, that just gets you the camera. You'll be adding quite a few things to that in order to get it working.
Price for a Phase One adapter is $1217, and the Canon mount adapter is $2061. Handgrip, which you'll probably want, is another $382.
I have to be honest and say that I felt the HCam was a little expensive for what it is, but obviously there's significant R&D costs in developing something like this, and volumes must be pretty low, so it is understandable.
However, looking at the price of the Alpa - $12,000 - $6839 for a B1i, or $8130 for the B1, actually seems pretty good value. Note that if you wanted to do a comparison between the FPS and the B1, then you'd have to add in another $1600 for the ground glass and focusing loupe.
At the end of the day, from my experience at Photokina, I have to say that if money was no option, I'd go with the FPS. This is a bit like a Lexus/Toyota comparison. Both cameras get the job done, though the Alpa is in a different class. But you do have to pay for it!
I'm fairly sure that the buzz around the FPS will get a lot more people interested in the capabilities of these cameras, and hopefully the market is big enough to support both solutions - Stefan really does deserve a lot of credit and success for what he's done with the HCam