I don't want to advocate a particular course of action, but I thought I would share some of my experiences.
I currently have an Epson V500, an Epson V750-M, and a Minolta Scan Dual IV.
I scan primarily C-41 color film and C-41 B&W film.
The V750 does a much better job than the V500.
With color negative film, I very much prefer the V750 results to the Scan Dual IV results.
Scandig rates the V750 as having an optical resolution of around 2300dpi, and they rete the Scan Dual IV at 3000dpi.
If I scan a very good slide film, this resolution difference easily noticeable.
If I scan color negative film, the resolution difference is hardly noticeable, but the Scan Dual IV scans always have a lot more digital noise than the V750 scans.
I've pulled my Scan Dual IV out many times in an attempt to get better scans, and almost always I prefer the V750 scan.
I have sold 12"x18" prints made from 3200dpi scans of 35mm with the V750, and to my eyes they look very good.
I scan a lot of 120 as well as 35mm, and having one scanner for both simplifies things.