RE: why not scale props?
On a 1/7th scale P-51 Mustang, a scale 4-blade prop would be roughly 19" in diameter. A 1.20 size 4-stroke can't even swing a 2-blade prop at that diameter, let alone 4 blades. The RCV 120-SP, which is designed to swing large multi-bladed props, can't even swing a 4-blade prop that big.