I'm getting 5.5 and 4.0 as every thing else is out of stock.
I drove Keefys SP5.5 and power is perfect for SMA... well for me anyway.
Ant, I'm going to SA title later this year. What motor do you use on 12th scale over there? Track looks very nice but hard to tell size from pics.
Ok as brad said there is little reason to buy big power motors as you will find very little use for full throttle. Last years nats was WON with a 4.5 at Whalan. This is with an exp driver who still though there was plenty of power.
Now for some quick facts... YES you can go faster in a straight line with more motor... BUT.. How much time do you spend in the turns? Even tracks like Whalan you still spend 80% of the lap turning the steering wheel. Because of this throttle control directly effects your lap speed.
The Moral is if you want consistent lap speed GET a motor you can handle. For most ppl on current technology that is around 5.5t even on big tracks.
Also stay away from LRP. They are easily the hardest motors to drive fast with too much bottom end. If you have to run one run VERY LONG wires to your motor to help prevent the motor from transferring too much heat to your ESC.