Depends on what you're looking for.... Not sure how many pple here scans their slides into computer. You tend to be particular about film grains if so. Digital might be very much more convenient solution to that. Even then, I'm comfortable with Kodak.
I've been using Kodak and the color is brilliant! I'm also a user of Provia films. I've never had problems with Kodak's grains (other than its notorious 400 print film!!!) Each film has it's own strength/weakness.... I'll vote for the E100VS. Excellent colors.
Sensia 100 with UV for Daylight, it has a built in warm tone, so it is not that blue.
Sensia 400 with FLD for indoor and night shots
I can't really tell the difference between Sensia and their pro counter parts. However, Sensia are cheaper and don't required professional storage. Velvia is still the best choice when I shoot flowers, althought it is a Pro flim I can't tell the quality difference between one that was exposed and developed immediately, and another that was left in the camera for two months before developing.