Michael, I've used it during over-cast Michigan Winter days & in the rain @ ISO 200 & 400; in the studio with Profoto strobes @ ISO 100; and @ all ISOs with a Hasselblad D40 Flash and various Quantum light modifiers... all to good effect.
In addition to the V Imacon Back, we also use a Kodak 645C digital ProBack on a Contax 645 ... which is a totally tethered free unit that uses CF cards for capture and a small but powerful clip on Lith battery; Plus, we use an original Kodak ProBack on a Hasselblad 555ELD and Mamiya RZ Pro II that also uses CF cards for capture, but requires a Large Quantum battery when not hooked up directly to the computer.
The 645C ProBack is the best of the bunch, including the Imacon, because it is totally tether free, and uses the excellent Kodak software AND is supported by Adobe RAW including all the latest upgrades.
So why did we also secure the V Back? Because it works directly and easily on the Hasselblad 503CW (thus extending the functionality of that most favored camera) ... where the 645C is a dedicated back for Contax 645C only, and the Original Kodak ProBack requires a lot of costly adapters and added complexity to be used on the 503CW. While the V96 has the disadvantage of being tethered to the Image-Bank, that is also one of it's strengths ... you can continuously capture 1000 RAW images without fussing with CF cards. Very good if you want to shoot unstopped like at a wedding or when pumping out catalog shots one after another without waiting for image transfer to a tethered computer. I've used it to shoot 100 product shots in rapid order.
IMO, the images from the Kodak backs and the V96 are comparable, with the edge going to the Kodak backs due to much better software. The faster you can get the Imacon images into PhotoShop CS, the better. The software sucks compared to C1, Kodak's Photo-Desk, and especially PSCS. In short, the V96 requires more post work to achieve similar results as provided by the Kodak backs.
Here's a V 96 shot @ ISO 400 on the 503CW using a 50mm @ f/4, taken in the rain during the Winter in pretty bad lighting conditions with no flash. I underexposed by about a stop, so it's similar to using ISO 800. There is some noise due to pushing the ISO and lifting the image in PhotoShop, but nothing significant up to a 18"X18" print (as large as my Epson 2200 Ink-Jet printer will go). In reality, I like the V96 images because they seem to "feel" more like film when viewed as prints. BTW, the blue fringing around the trees to the left is not apparent in the print, but instead a result of compressing to a 790 pixel wide, 125K J-Peg. The print is fine.