Which Brushless motor

[ashleyb4]

Im getting a brushless system for my xx4 for my birthday. But Im stuck with which motor to go for everyone is saying 5.5 4wd 6.5 2wd at the moment im favouring the novak system with sinitared rotor but as im only a novice driver i dont really want a really fast motor so i was wondering do i go for a 5.5 o a 6.5 or even a 7.5 as i have learnt that slow is fast. So i would like peoples opinion's on this??? Should i just get the 5.5 or get a slower motor.

A