I built about 14 of 'em. They were a great kit combat plane, provided you put the engine on the centerline, not elevated like in the kit. It was a Top Flite product, but I don't recall any mention of the designer. I always figured it was an in-house knockoff for the Flite Streak.
Lots of other designs, like the VooDoo were undersize with the G21/35 and the wing area of the Combat Cat came in handy.