I've only had a bit of time to mess w/ it but - that thing is fun! I didn't try all the models that much - after a quick round through the presets, I went back to manual mode, selected the JT-45 model - a likely candidate to get the kind of tone I like - and tweaked from there.
Loved it, loved how dynamic it was - there's even that sour transient at the beginning of the notes, that little surge that's so often missing from amp models.
And I'm glad to see that I can do my tweaking w/o the need to use software - switch cabs, mics, browse through reverbs, etc. Having read the manuals in advance and being familiar w/ the Spider line of amps helped me feel at home w/ the new POD I guess.
Overall, a dramatic improvement over my old POD 2 (obviously) and better than the Spider, which tends to sound more like a bunch of static presets than actual amp models.
Anyway, cool new toy.