I have launch control on the M3 - it is fun, but not something you would choose to use with any regularity, I would think. In the M3, one can lauch at different rpm - once in launch mode, you can alter the revs to which the car goes up to - from 4500 to 6500, I believe, in 500rpm increments. Not sure if the ///X Ms have this feature??
I think I've used it once only. It's way more fun driving on the track
A 4.1 second 0-60 in a 5000lb+ vehicle has GOT to be an eye opener