Does anyone have any idea about how many Rotary engines are in use in home built aircraft here in the U.S.? Does the FAA keep any records on this? What percentage of the Experimental aircraft fleet are powered Rotary engines, etc.? Seems to me that IF a large number of Rotary engines were being used, then there would be a lot more companies selling PRSU units for the Mazda Rotaries. THANKS! P.S. Who does make a good PRSU for the Mazda Rotary engine?