I have gotten into the habit of using my HD500 (not the new X) for rehearsals with basic marshall and fender presets and delays. Sometimes I'm frustrated that it sounds as good as it does on a rehearsal recording!
Then, I go home and practice the songs, and program my Axe FX, and it is sooooooooooooo much better, I don't care anymore about the rehearsal CD sounding respectible.
I watched a video of Dave Navarro who was on tour with Riahnna and he said "the modelers sound pretty good until you immediately play the real amp right afterwards".