Hasselblad Flextight is the high end.
Hasselblad link. Not much in the way of new technology here so look for a deal on a discontinued model or a used model (mine is a 343). They are very robust. I had an issue with mine, sent it to Hasselblad and had it back within a week. It uses proprietary software, FlexColor, which is very flexible, but has an odd interface so the learning curve is quite steep. I have some question as to Hasselblad's long-term commitment to this product, as this is a shrinking market. They were very slow coming out with a version that works correctly under the latest version of OSX (or maybe OSX was fixed to accommodate legacy stuff - I forget at this point). One plus with this system is that it handles MF (or 4x5 if you buy one of the larger machines that handles 4x5), so you would be in business with a Mamaya 7 II, which you can buy for the cost of a Leica lens shade.
If you have thousands of rolls of legacy film the Flextight is slow. You set up a strip of five frames in the flexible negative carrier and feed it into the machine, make whatever adjustments are needed in terms of image quality and it then grinds out the scans.
For volume work you might consider a flat bed. I believe that the Epson V750 is still viewed as an outstanding quality/price point. The software of choice for it is Silverfast. The pro model of the V750 comes with a holder that permits fluid mounting - this results in a dramatic decrease in grain and makes most dust and scratches disappear. You need to buy fluid mounting medium and cover sheets separately. The pro holder is not very robust - it is made of a plastic that tends to disintigrate around stress points. I haven't seen much reference to this online, which makes me think that not many people are actually using the fluid mount.
The dark side of scanning is dust and scratches. You need to work very clean and even so you end up doing a lot (and I mean a lot) of hand spotting in PS. The cost of "art" is mind-numbing tedium. The Nikon scanner that Jim uses has hadware and software that recognize dust, but I had only so-so experience with it and ended up selling it to buy the Flextight - I'd be interested in his experience on this. Hasselblad offers "Flex Touch" software which supposedly deals with dust, but its a $400 add on and I haven't bought it because I'm frankly skeptical about any software only solution to this surface (the Nikon scanner separately scans the surface of the film looking for dust) and there's no evidence of ongoing support for it on the Hasselblad site.