I had the GTI lowered and put on a set of summer tires.
Specs: 18 x 7.5 BBS Hufweisen wheels (OEM) et 51
H&R Supersport Springs 1.9" F/R drop
Koni Yellow Shocks/Struts
Ride is slightly stiffer than stock. I was execting a lot worse with this drop but I guess the stock GTi suspension is really firm. Barelly any difference. I love it.
I didn't wash the car yet and these pics suck but here is before and after.