If the x3 is cheaper or even the same price I'd go for that. The only possible downside I can see is the extra rack space it will take up, but who cares. It's pretty much like 2 pods in one. You could use it for scratch tracks of two guitarists simultaneously (I'd assume, from what I've read about it) or stack two different "amps" on top of eachother for more tone possibilities. Even if it's the same technology as the xt, it has more options, so you get more for your money. You could also plug mics into it for weird vocal shit if you wanted. I'd say go x3. Especially if you can get it cheaper.