ok i own a Gibson SG and i am wanting to score a great tremonti tone... like in the song Down To My Last by Alter Bridge... i want that clean guitar tone with Metalingus type distortion... any suggestions on amps and some like pedals?
I think Tremonti uses a Klon Centaur, and he definately uses a Mesa Triple Rectifier live, along with using Dual Rectifiers in the studio and stuff.

Theres a video outlining his gear on youtube somewhere.

TBH I'm not that good at pinpointing how much an SG will sound different to a PRS, but its bound to be an important factor.
mesa rectifier + PRS guitar

the same for nickelback, theory of a deadman, and all those bands