If you are racing, you will be spending some time with the car and therefore need to know how it works, hence a kit.

If you are bashing, chances are you wont need to fix it too much and an RTR might work out cheaper.

Also, buying a kit doesnt tie you down to the electrics supplied, as there are none Even if you cant buy the most expensive or preferred car, you can still buy better electrics from the start should you want to.

Downside is, if racing isnt for you and you got the more expensive stuff, then you've just blown quite a bit of money.

You've just gotta work out whats best for you, get yourself to a track a few times and see how things are, hang around for a chat with people and ask a few questions if need be