Confused about motor range

[KiZ]

Hi guys, I think I'm going to have to get someone to explain the range of motors available to me, I have just got really confused trying to work stuff out. I have read a lot of the threads here and spent a fair time researching this, but I cant get it any clearer.

I don't have a large amount to spend, so I presume Feigao is a good brand to go with?

1. What is the difference in the number of winds in the motors?

2. What is the difference between the normal 540 motors, the 540c motors, the 540c XL, etc

3. Why are Lehners so damn expensive?

4. What would be a good motor and controller to go with? I have a savage, roughly stock weight that I want to convert. I dont need it to be blisteringly fast, and I have a medium budget, but I still want it to be able to at least match its current nitro config (~40 mph and wheelies). Is that possible? I already have a 3 speed and lightweight dirtbonz tires if that helps...

Thanks guys ^^