personally speaking I'd go for an amp that doesn't do modelling, and have a separate set of pedals (or 'pod' – multi-pedal) (like what grumm said)
One of our guitarists has a Mesa Boogie amp & separate pedal board, the other guy has a Vox AC30 & separate pedal board. The AC30's knackered though, so he's just ordered a 'powered speaker' (4×10) and will rely on his effect to change the sound
the bass player has a choice of Hartke & Trace Elliott heads and separate speaker cabs. normally he brings the Hartke head & a 4×12 cab, but last week he brought the TE. It sounded soooo much better :-)
but what do I know, I'm only a drummer ;-)