psykikThis one is 3800kv, with a longer can, meaning it has more torque than the 5700kv model on Amazon, which will give you more punch off the line. This also allows you to gear it a bit more aggressively with less risk of overheating. The 5700kv should have a bit higher top-end speed, but generally the 3800kv is more versatile, and can be used in a bit heavier vehicles.
http://www.amazon.com/Castle-Creations-Sidewinder-Waterproof-NC1406-5700KV/dp/B00AQYMNE6/