Considering all the built-in effects and diversity of tones, it's just a really great amp. It takes a little reading up before you can use all of the features and I'd really recommend getting the pedal as well. I've mainly used this one with a Harley Benton CST with P90's and I have to say, with all dials at 12 o'clock, this can sound pretty darn incredible.
At this price range, I kind of feel like I do have to compare it to the cheaper tube amps though. I just went to a store that had an H&K Tubemeister Deluxe 20 ready for a test, and in the end, none of the tones on this Katana can compare to the juicy crunch of the Tubemeister. Yes, you'll have to get your own effects, but I decided to get the H&K anyway and sell this one.
All in all, I think Boss has made amazing progress in the field of solid-state amps, but it still can't compare to tube crunch, and I'll still pay a few bucks extra for that.