The best 'modeler' I ever played - and also used for years live - was a Marshall JMP-1 preamp via two different speaker emulators mixed together and thru a Boss SE-50 multiFX for some ambience (verb) into PA...it was VERY good for any use, nothing like the usual POD saturated FX laden stuff, but very very close to a full tube rig.

I did use first an SS poweramp and a 4x12" with it for monitoring, and later a 60W all-tube Peavey Classic poweramp and a 4x12"...still went to PA from the D/I outs and it was very good. That was what I used for Crankenhaus for a good while too.

But, can't beat the 36W head I now use...now that is real punch to play in front of :-) and that's what I have on Spookbox demos.