I've tried this several times over the years, with a variety of vintage amps. It's great, on stage, for the player. However it creates a bit of a conundrum for the the sound guy as he can't always know which amp the player is hoping will be featured. When I do sound and a guitar player shows up with a two amp setup, I don't get too excited over it. Nearly 40 years ago I had a tech modify a Morley pedal into a pan between two outputs, each output to a different amp (blackface twin and Marshall super Lead). That was a pretty cool and unique setup. And really loud!