Just cranked it!
The speakers need a bit of breaking in still, they seem to have a decent bass response for vintage type speakers and more treble than I expected. I will have to dial my amp in on the fly tomorrow at the gig as my settings for the 2x12 with V30's dont sit right with the cab.
Im sure after I get used to the change (been playing V30 loaded cabs for 4 years) it will grow on me, but it definately has the raw ingredients for awesome tone!