I've had a V700 for years, used primarily for scanning film (mostly negatives, some slides). The results were usually good unless the film had a "bow" or curl and wouldn't stay flat in the carriers. In recent years it would also "lose communication with scanner" and Epson Scan would close - sometimes several times for 20 frames.
The 850 is faster, has glass carriers to hold negatives flatter, and has yet to lose communication during a scan. I'm very pleased.

Together w/SilverFast software, it does a great job scanning 4x5 and 220 film.

This has made a big difference in my work with film. The difference between my scans and what I was getting from the local lab are night and day difference!

This has made a big difference in my work with film. The difference between my scans and what I was getting from the local lab are night and day difference!

The start up and scan times are pretty much as advertised.  Most of my 35mm negatives, and slides scan in just over a minute--at 4800 dpi. Im not crazy about the film holders though. The glass theyve inserted is another surface to have to clean and try to keep dust off of.  And the film holder reinforcement theyve introduced for the slide holder makes it more cumbersome to remove the slides from the holder. I have resorted to using the film holders from my old Perfection V750 Pro. Other than that, Im thrilled.

Not only getting my old film-based pictures ported over to digital for archiving and viewing on computer or TV display, but having fun doing it. I own an Apple iMac computer as its interface and it DOES work with the latest iMac OS, Catalina. (However, a couple of non-essential features are currently inaccessible and I hope a future Epson update will fix that.) I'm getting some extremely detailed and accurate scans of old photos, and there are even some image improvement features that are not hard to master, to plus up shortcomings in your originals.

Incredible scanner, in using either the Epson software and even more possibilities using the SilverFast version tht came ith the scanner. I have thousands of 35mm, 6mm x6mm, 6x7 and 4x5 film to scan for my image library archive. I am mostly scanning images to print on canvas and mounting as Gallery' wrap.

after finding out that the labs i use here in NYC were using this scanner for any high res flat work i sent in, i purchased one to begin scanning the thousands of test Polaroids ive saved over the years. I even figured out a way to scan sx70 and spectra Polaroids without getting newton rings using one of the many neg holders that come with the scanner. Since i was paying 25-75 a scan before, this thing paid for itself within a few days.

I bought this scanner for only one purpose, scan old negatives from WWII. My father was a Army photographer and had file cabinets full of personal negatives that had never been printed. Over this winter I will be scanning some of them. The little I have used the V850 so far it has done a great job. But I still will have to learn the software's capability .

This is the review that I hoped I'd be able to give when I started using the v850, and the review I wished I could have read when I was the one shopping for a scanner:

Besides professional drum scanning, this is as good as it gets for large format film scanning. I scan 4x5 color negatives. I use the included silverfast software in wide transparency mode and put the negatives directly on the scanner, emulsion side down, with a piece of anti-newton glass on top of it. This uses the lower resolution lens, but you don't need to go higher than 4800ppi unless you are making truly massive prints (I usually scan at 1600ppi. The file size for a 48bit image is around 300mb, and it's suitable for an excellent print up to 20x25". The flatness of the negative and the clarity achieved with this method are the best I've seen, short of a professional drum scanner. You have to be extra careful to avoid finger prints, scratches and dust with this method, but unless you are filthy rich or have only a small amount of film to have drum scanned, you will not get better results any other way. I highly recommend the scanner glass cleaning kit that B&H recommends as an accessory. Another hint, if you don't know: you don't need to worry about color calibration software and targets if you are scanning negatives--it's only relevant for positive transparencies and reflective scanning. The negafix tool in the silverfast software uses the correct color profile for the negative film you are using, and you can further adjust these profiles if you want to.