Henry, I used this back about 2 months ago on a Hasselblad 503, some images (full resolution) are here;
http://www.stoqq.com/sinar-test , also
http://www.stoqq.com/mavs06 (not full res). I think it's a fantastic back, delivering wonderful results, worth about $20-22k now as the 33Mpix is coming out. One thing that it does do is show you just how crap some lenses are. I used it with a 500mm hasselblad lens, the chromatic aberrations were rather extreme. My thoughts and reason for not buying it are;
- It's a 645 frame size, so, you need to use a fiddly mask on your waist-level viewfinder
- You can't use it with a PM90 prism (the back is too deep and clashes with the pm90)
- The software is Mac only, no photoshop CS2 / Bridge support yet
- 2.2" OLED screen is too small for me, although it did quite well in bright sun
- You need to use a sync cord from your lens to the back, so, any external flash or radio slave you want to use (usually mounted on my PM90!) is a bit trickier to mount
My recommendation is to use an H1/H2 with this back (who else is left!?), not the Hasselblad V, you really need the autofocus, the 645 aspect ratio and the auto exposure that the H1/H2 gives. Even if you're slightly off focus, the back is unforgiving in showing you just what a crap focussing job you did.
Lastly, I know it's a remarkable feat of engineering, (the best 22MP back out there) but it's simply too expensive and not good enough (noise wise) above 100 ISO.
-Nik