Superb scanner for scanning film. 4800dpi optical resolution is enough to show unaliased grain on tech-pan! (albeit with 0.75GB output files for 5x4...). People complain about flimsy film holders but I find they work well, especially for larger formats. Film flatness is not usually a problem as the scanner has a good depth of field. The only problem I've had was with very curly unmounted slides - if they touch the glass you get newtons rings in the highlights, but this roll was particularly curled in processing.
If you use more than 35mm formats then this scanner is perfect. The quality of output is equal to a drum scanner costing £000s. Density is good enough for all but the toughest slides - if you want more black, buy the 4990 or V700, but its very rare to push it to the limit. With black and white negs where density is rarely more than 2.5D you have very good dynamic range without quantisation artifacts in white areas.
Epson scan software is excellent and I prefer it to the silverfast software that is bundled. You have full control of the scanning process with simple controls that work very much the way you expect if you are a photoshop user. It allows you to decide how the scanner clips highlight and shadow detail. Scanning is as fast as you could expect at 4800dpi
Colour on negative scans is generally excellent with no casts from the film base.
Overall I'm very happy with the performance of this scanner given its very reasonable price. 4990 and V700 dont offer much more ,other than Dmax of 4.0 - 4800dpi is enough - howmuch disk space do you want to use per photo?? 6800dpi is overkill even with super fine grain film.