Selmer had the radial 2 degrees valve cluster. I talked to Bauerfeind a while back about this. My idea was a 4 valve piccolo. They said that it is very tough to build those valves because after everything is soldered together, you have to grind and polish the inside of the valve casing before lapping the valves in. Conventional maschines can't handle the angle so it gets real expensive. You also have to think about the valve caps being removable at the bottom where they are VERY close together. I have a early 70's Selmer Radial D/Eb. The design works. In spite of MANY hours of play, there is little wear on the valves.