It wasn't that long ago that all the pundits/users were just peeing their pants over the Ultra introduction, and it didn't do anything but get better from there. The introduction of the AxeFx II and it's successors just added more accuracy from a modeling point of view. That doesn't take anything away from the Ultra, it just meant that a [insert amp model here] sounded more exactly like a real [insert amp model here]. It doesn't mean the [insert amp model here] model didn't sound good before; It just wasn't a perfect copy like it is now. Still sounds fantastic, though. When you consider that most older tube-based amps were pretty variable in their performance right from the factory, who's to say what's "accurate"? I'm confident that the current models in the latest AxeFx II sound just like the physical examples Cliff has in his studio/lab, but I've owned enough amps to know that they're as individual as the guitars we run through them, particularly when you're talking about tube-based designs.
Given all that, the Ultra is still a fine piece of gear. I seriously doubt you'd be disappointed with the thing unless it's important to you that the models be dead-nuts perfect mirror audio images. Even then, remember that a LOT of guys were selling off large collections of premium vintage amps and effects once they got the Ultra. Then, even if you don't care about the amps, the effects are tremendous and numerous.
For 800 beans, you may want to jump on the thing. That kind of money won't buy you a real amp that sounds as good, and you'll get a big pile of amps and effects all in one package.
