Although I use it on track, I'd say I do 10% track driving and 90% road. At the moment my car is 100kg lighter than standard, when I'm done with weight loss it'll be around 940-950kg with me in it and a full tank of fuel.
400lb springs are enough on the front for me, especially with the weight loss. The Bilstein have good damping control to match the spring rate hence they don't feel stiff but the springs are what really control the roll.
The rear springs are only 225lb or thereabouts which is very soft but nice on the road given that the car is light at the back and won't make the back end step out. So I'd be upping those to around 450lb for track or I could keep the softer ones for wet days.
However there is a chance (although I suspect an infinitesimally small chance) that the ASTs could turn up tomorrow. We shall see!