Well Looks like an older thread but here is my .02

The Jett is the finest sport engine on the planet---- but assuming you are shooting < $260 The Webra has the fastest throttle response I have seen- it is light, runs on 5%, and is easy to tune---

The Irvine-53 is a slam dunk for torque and big props. but did not transition as quickly as the Webra (Your results may vary--)

Cheers!