The Epson Perfection 4490 was purchased primarily for a very, very large scanning project to digitize 35mm slides. Many of these slides date from the '60s, '70s, some from before, and some after. I am VERY happy with the results I have gotten from this scanner.
Many of the slides I have are discolored. I have used both the automatic "color restoration" and the Adobe Photoshope Elements software that comes with the scanner, and both work decently, though Photoshope does work a bit better for slides that have faded to red. As far as the other software that is included, I have looked at it, but will probably never use most of it. The Presto! Biz Card can be used similar to Microsoft Access as far as organizing your business cards, if you have a lot of business cards to organize, and don't want to keep a hard copy anymore.
As far as the dust removal, well that doesn't work as well as I'd thought it might, but I didn't but such high expectations on slides that I didn't bother to clean that are almost 40 years old! The glass is more sensitive to fingerprints then other machines I've used, but they didn't show up on the scanned images at all.
I do wish that the scan area for slides/negatives was larger. As it stands, there is only space for a single strip, which amounts to 4 35mm slides, but I guess that machines costs a heck of a lot more. But they scan relatively quickly and I've been able to get through quite a few in one day, with touch ups! Wonderful machine for photos, and after 6 trays of slides, looking forward to another 90 trays or so!