Which Lehner Motor for my E-Revo???

[Hickoryhead]

I am a perfectionist. I had to buy a new radio because the stock one I had for my BL Stampede was jerking around the truck. I don't understand it but the ground was harder than the radio. LOL I don't want cogging to happen so I will stick with Lehner. I am not satified with the reports of the customer service from Lehner but its what I run in my other RC's. They work great for me. I hope Fine Design works out.

As a side note whats the difference between a 7 turn, 8 turn, or 9 turn motor? Say the motor is a 1940.