i have the Epson V500, love it to death. Have some images uploaded from it if you want to see. 35mm film. I develop my film at a local pharmacy and then scan it myself, its worth it because i could never find a company that would scan it at the resolution I wanted and when I did it was about $30 or so a roll, way to much. The V500 will scan at resolutions higher than you will ever want to use.
While it's out of budget, I second the Plustek recommendation. I have an Opticfilm 7600 (which is a dedicated 35mm scanner), and it works fabulously. It also comes with a free copy of Silverfast, which is essential for scanning in my opinion.
Maybe you could show us any results ? I'm scanning photographs ( not negs ), with my printer, decent quality in good resolution, what would be the benefits of a film scanner ? Moreover, the scanners you're talking about have a resolution of 5 mpx, no ?
Flatbed scanners have the light source and CCD on the same side of whatever you're scanning, and work via reflected light.
This doesn't work for negatives (or slides, for that matter). Those require the light source to be behind the negative and shine through it to the CCD on the other side. This means either a dedicated film scanner (like the PlusTek OpticScans) or a flatbed scanner with a transparency adapter (like many of the the Epson Vxxx series)
In theory you could have everything printed and then scan the prints, but that involves both a potential loss of quality, and making or having made prints for every frame, which has costs in money, storage, and possibly effort.