I run my VAs on 15%, bladder pressure, and they do pretty well. I guess I oughtta pick up some higher nitro just to see what they're really capable of. Surprisingly, for a relatively high-performance engine, they hand-start easily. They love high rpms and they're loud. They weigh about 2 oz., same as Norvels, BWs, etc.; fairly thirsty (power has to come from somewhere) and rear exhaust, kind of a problem on profiles with a tank sitting behind.
Beyond that, I can't tell you much more about them. I don't know where they're made. Picked mine up in a package deal from another guy.
--Ray