Best Tube Amp For Heavy Metal That Is Under $1000?

Basically, i'm looking for an amp (head or combo it doesnt matter) that can REALLY shred, but has to be under $1000. I play alot of Metallica, Megadeth, Slayer, Ozzy, etc. I've been looking into the Peavey 6505+ combo, so if anyone owns one, an opinion on it would also be cool.