I've been shitty about actually answering questions; I'll give this thread a run through when I'm out of class in a couple hours. It has a ton of built-in FX and more get released with the updates. So far all it's missing FX-wise that I'd want are a harmonizer/shifter/octaver, but that's high on the user request list over on the Kemper forum so I'm confident it'll get put in the next one or two update cycles.
The cleans rule, it really depends on how well you model the amp, but it all responds exactly like you'd expect the amp to. Bass tones have been profiled, and I have a few SVT/8x10 patches I haven't actually tried out yet (AmpFactory, so they should be good); my bass has old ass strings on it but I'll try to post some DI/kemper SVT comparisons, unless someone wants to link me to some awesome bass DIs.