Well, the c50 motors come in all different sizes and winds, just like the feigao 540 class motors. The c50 maxx is a hybrid of a l can and a s length rotor. It has a kv of around 3000 and should produce smilar power to a l can feigao with better effecientcy.
I have a 13l c50 in my ls10. I run it on 5s 3000mah lipo and a quark 65. It is geared for about 45 and it runs cool. I would say that a c50 l can is compareable in power to a feigao xl motor, and will run cooler.
I may try a c50 15l that I have in the 2wd old emaxx, and see how much better it is than the feigao 15l I currently run. The hacker is a much better made motor and I have had excellent succes with them. The c50 is a bit large in diameter, which can cause some fit issues.