have you tried one with a 12 tooth as stated?
Yup, that's what I have in my shark and I have a lot of flights on that combo. I like it better than the stock motor. It seems to have plenty of head speed when throttle curve is set mid point (normal at 55%, S1 at 75% and S2 at 85%. It climbs very fast and has no problem powering out of things. The fff speed is great and it handles the wind well. They don't cost much (i think they are only like $19 or so) so you don't have much to lose by checking it out. If you don't like it, you can always put it in a falcon.. but I'm pretty sure you will like the performance of it. It is a smaller "looking" motor compared to the stock one, but don't let that fool you. If for some reason you need or want more or less pop out of it you could adjust the throttle curve and/or swap to a different pinion (11T, 13T). I'd love to hear what you think of it if you decide to give it a shot.