Mechans is correct. I may have overstated the impact of simply moving from solid state to tubes in that a well designed solid state amp will likely sound better than a poorly designed tube amp. However, if you do end up going with a VAC integrated, I'm confident it should be an upgrade from most if not all comparably priced solid state integrateds.
What speakers do you intend to use and which VAC integrated would you pair them with?
What speakers do you intend to use and which VAC integrated would you pair them with?