Hey mesh, I have the 4990, which the V700 replaced. I think you'll be quite happy with the results overall, even with the Epson Scan software. I actually prefer it for general scanning purposes over VueScan and Silverfast. Neither are as intuitive or as easy to use as Epson Scan is.
I have found that my 4990 does such a good job with medium format scans, scanning at a "mere" 2400dpi, that I honestly don't know why I'd feel the need to use another scanning method.