PHOTOBOYDC  We started using VueScan Pro version instead of SilverFast with a flatbed Epson 1680 to scan sheet film because it was so much faster, although cruder in its interface. It did not take long, however, to see insurmountable quality problems in the scans...lots of grain, and not too sharp, and rather abrupt roll-off in transitions from light to dark. Several days of back and forth with the developer did not solve the problem. We did side by side comparisons with VueScan and Silverfast and the difference is, unfortunately, instantly obvious (if someone tells me how to post jpeg examples in this forum I'll be happy to post the comparison). There is also the problem of very limited control of the curve; you are given two points of control versus perhaps six with SilverFast.

It's obvious there are a lot of happy VueScan users out there, but if you are a serious photographer making large, sharp prints, or if you want really accurate control of the contrast curve, this software may not be for you.  
(Version 8.5.06)