"Air bags or coilovers are more for show with less performance"
Thats partly true. Air bags are for show. Your handling will GREATLY decrease with bags. Coilovers on the other hand will improve your handling. The springs are stiff, and if teamed with the proper struts, it can be a great setup. The adjustability is nice, but, realistically, how often will you actually change the height?
Now, I have Eibach springs, and I love my suspension setup. If I had to recommend springs that are performance oriented, i'd say go with Eibachs, Roush or H&R. If you just want a nice drop, go with Intrax or B&G. If you want good performance with the advantage of adjustability, then Ground Controls is the way to go. In the end, it just depends how much you want to spend, and what your goal is.
Mike