I'm one of the resident Audio Valve champions on Audiogon, so I figured I'd put in my 2 cents here. I have the 50 watt ppp45's, and I absolutely adore them. They are maintenance-free, look really cool, and they sound great. I can't comment on the model that you're looking at, but I can tell you about their lower-powered models. They are DEAD QUIET (you can put your ear right against the tweeter and hear nothing). They are extremely detailed (not the stereotype for a tube amp), and have a remarkably tight bass when connected to the right preamp. (I've tried several preamps and for my listening tastes I prefer mating them with solid state preamps.) They've never sounded strained -- and we're talking about only 50 watts here.
Now, the downside to Audio Valve products: They are made in Germany (that's good) but have a less-than-ideal US distributor (that's bad). They also suffer from name recognition problems. This will work to your advantage as a buyer, and to your disadvantage as a seller. There is also a very limited network of dealers in the USA.
By all means, I recommend auditioning them and you can see for yourself if they make you as happy as my pair makes me.