i got mine setup with a martix magnum motor, it seems excellent lol but i am also running the 20:15 dsg set.
My current setup is, G&P 9mm ball bearing bushings matrix magnum motor, 20:15 cyclone set, shs purple metal toothed piston, short stroked, and lightened with a modify PC piston head, 3/4 inch spring spacer and m170 spring.
With custom mosfet. On a 7.4 35c its around 45 rps, and with a 11.1 40c 5000 mah its 73.33 rps.
there defanatly somthing different, the Stresses on the internals are pretty extreme. and even finding a good barrel to go with the setup. there defanatly alot of fun to work on