i've got Weitec Hicon GTs. the only thing i can compare them to is my stock S-Line suspension and it's slightly more comfortable but you get MUCH less roll. they probably don't improve the handling but they certainly give you much more confidence to fling it about. i got mine 2nd hand and paid £400 for it, and paid £275 to fit from Midland VW in Cannock (top blokes btw) with a full 4 wheel alignment. they've totally transformed my car, i'd recommend them all day.
best of luck in your choice!