RE: 380 AND 370 GEARED UPGRADE
You could upgrade to Cobalt motors, but your improvement will not be dramatic. The obvious, but more expensive, answer is to go the brushless route. For the direct drive you could use one of the outrunners (Nippy/Freestyle/PJS 550 etc); for the geared one use an MP JET 25/25 or 25/35, or a Razor with inline or GWS g/box. Lots more power, lots more durability!
Cheers, Phil