Actually, it's my Crate that's for sale.
With an 8 ohm cab, you'll probably get more volume out of the Crate for sure, but from the looks of it you might get more tonal options with the Peavey. (ie: the 't.dynamics knob, the mid scoop switch, etc..'. At the same time however, if you throw an EQ pedal into the fx loop of the Crate, it can be a gain machine. I've never heard one of the Trans. Supreme heads (I used to own the Supreme XL) but what I can tell you is that the Crate definitely DOES have enough gain for metal.