I caveat this with the fact that I am a newb bass player...
Last night I hooked up my Tube version to an Ampeg 8x10 classic fridge.. wow.. just wow.. very warm and full. I play melodic rock, some upbeat stuff some ballads.. ("Seven More Days" blatant promo). I can't profess to have given it a full work over eq-wise etc, but at a very flat eq setting it was excellent.. and very very loud. It cuts well and very clean. I've only touched on what this can do I'm sure but immediately I had results.
The rest of the band were stunned, and commented on how well it sits, and previously I was borrowing an Ampeg SVT classic valve head!!!!