Therein lies the rub. You can't beat real circuits and valves especially when you're cranking it loud for a gig. The difference between the (admittedly pretty amazing) VST's and the real deal is the difference between sounding good and sounding great.
Touring a band is still expensive. So much so that it was the difference between going on extensive global touring as a duo or not touring at all (4 piece) for someone I know.