Dont have the cash for the H-sports, but thought the s4 would be a nice upgrade from my non-sport 03 A4 setup....just wondering if there is anything different about installation other than droping exhaust removing old 16mm and then putting the s4 one in with bushings??? Thanks!

the rear sway on a base '03 is 14mm, the S4 sway bar, on a B6 S4 , from 2004 is 20mm and makes a huge difference in the handling dynamics of your car.