different props perform differently on every different type airframe and what works great on sport plane X may not be the best on the same engine/fuel on trainer plane X, also ground RPM, or static thrust, is absolutely no indication of performance so saying 'Prop brand XX is a dog because it turned less RPM then brand XXX on the ground' is about as un-scientific as you can get.
the more efficient prop will always turn less RPM in a static situation because it is grabbing more air (therefore more drag on the prop). MAS props flex and flatten out (loose pitch) when brought up to RPM, a 10x6 MAS when at 12K+ RPM flattens out to less pitch, 10x5/10x4ish. APC props with higher pitch tend to stall more when held in a static situation and in flight performance (dynamic thrust) is the deciding factor and I'm very surprised that you got more speed with the same diameter/pitch MAS or even the Zingers then the APC. myself and many others haven't had the same experiences. might be an east coast v/s west coast issue
I never flew when i was in Cali myself, i just can't bring myself to fly off dirt/desert (there wasn't any grass where i was at) and they didn't have any paved runways that allowed for RC flying back then. (Lemoore NAS)
kc