Hey, I currently have FRPP C springs on my 2003 GT mustang. I love the ride height but the ride is a little rough. I am planning on getting Bilstein Struts and Shocks and MM Caster Camber plates soon. I know the H&R are stiffer and progressive vs. the FRPP springs. I was wondering if anyone can put thier 2cents in if they have experience with these springs and which ones would work better for street use and maybe a supercharger one day?