The CC 17/17 would have more torque than the other.
The 1521 would have a little more torque than the 1520, as its rotor is a little longer, but they are very close. Maybe the real neu is the best one for efficiency and weight.
Other than that theses three motors are beasts in 1/10 MT like E-Revo
i am pretty sure i saw on the castle site that the 1717 is 50mm dia motor. much larger and heavier than the 42mm 1520 or 44mm neu 1521. so as stated, it will have more torque. might be too big to get in a revo.....and way overkill. but hey, have fun!
Jammin SCRT10 Neu 1512 1y
Losi Ten-T SCT conversion Neu 1512 1y
The 1717 will drastically limit your gearing option in a Revo, if it will even fit. The 68T spur would definitely be required and I don't know what the minimum size pinion would be just so they actually meet
Well the 1717 motor has a fatter shorter stator. So it will have more toque, but not sure if it will output much more overall power. I have ran the 1521 1y neu in a few big trucks and was satisfied with the power. I also have a 1717 that I plan to run in my lst. Not sure if it will be any better, but it should offer more torque so bigger tires will not pose a problem.
I like neu motors, but have been impressed with the cc 2200, and hope to be impress with the 1717 as well. We will see.
I see no reason to move away from the 1521 1y, unless you plan to go to a 1527.