I have and use Amplitube 3, GTR, Pod Farm, and don't forget Acme Bar Gig. I don't have ReValver but have used it in other studios. It is very impressive. I am really liking what I'm hearing with Scuffham. It sounds warm and natural to my ear. I haven't had time to really blow thru TH2 yet as far as tweaks but it sounds pretty good. I have to say I prefer Amplitube over GTR. GTR sounds very harsh on overdriven sounds. Amp 3 sounds a little rounder. If I work on a track I know is going on to a record, I break out the amps and mics. The amp sims make life much easier but I am afraid they will never beat the sound of a good tube amp with the right mic and the right positioning. I use the amp sims to flesh out the demo but if it goes to a record 9 times out of 10 it will be the real deal. If I were going to use one or the other sim it would be Amp 3! Drum roll, please............. Amp 3, Scuffham, Revalver. Pick one.