what is the advantage? besides changing the ride height?

 

I think that's it.... I dunno

 

be more specific...if you are talking about the advantage of coil-over sleeves, then the answer is ride height adjustability, the ability to corner weight the car (important in racing and autoX), ability to pick you're own spring rates. You're car comes with a coil-over suspension from the factory BTW....coil-over=coil spring over a shock