Still learning, I'm trying to find out what the Y/D spec rating in the motor P/n's is I keep seeing. I understand Kv,max rpm, watts, most all the rest. Another thing why is a 2200kv Neu 1415 3x more expensive than a 2200kv leopard? The Neu is a 1y the Leopard 3D most all the other Spec's I have...