depends on what springs you get and how you want it to ride Ive gotten the Ebiach Pro kit for my car I havent installed it yet but Ive seen car's with it on them and it looks pretty good heres a URL to a good site http://www.latemodelrestoration.com/products/Mustang-Spring-Kits
Fo Sho. But I just picked up a set of 1month used springs from a guy on CL and that was 100 bucks as opposed to 240 new. On the other hand you can buy a nice coilover set for well over 1000.
I have the Eibach ProKIt complete suspension & it dropped 1.5" all the way around...gives it a great stance but a fairly good ride & some clearance still.
I know the Roush suspension rides much nicer! I have not tried other combos so you might be right...it only hits hard on bigger bumps just firm on the rest. Roush was silky smooth for most conditions then firm to hard on bad bumps. If I did it over I'd def. go Roush for me.