I've used just about every 35mm scanner out there going back to the Polaroid Sprintscan 4000, no ICE and a SCSI connection, not Firewire or USB. The Nikon 5000 wins hands down ( I used a 4000 for a long time and liked it a lot. the 5000 is faster and quieter). Some are as good image wise (Minolta 5400, but where are the parts if you need repair???), but you can't find another that has the SF-210 Slide feeder.
Take a roll of film and shoot. Get them back from processing and put the whole roll in and off you go. Scan at a low res and view the results in a very short time. Now I don't know about you Guy's and Gal's but I feel real lucky to get a few good shots off of a roll. Now you take those and run them through, 1 at a time and make the adjustments and you end up with a real good digital image. Close to an Imacron scan if you use the fine setting at 16x sampling, but 1/5 the price.
With Medium Format, you have to have a glass film holder, regardless of the type of scanner, or the corners will be out of focus. Used a 8000 for a time, but got frustrated and got rid of my MF Gear and the scanner
I used Vuescan and Nikon Scan. Liked Vuescan more at first, but after the learning curve, now only use Nikon Scan.
Hope this helps on the 35mm end of it.