Ride with shocks on full soft is better than stock believe it or not, but I've bottomed out a few times going over huge bumps on the freeway at 65 mph. It shouldnt be an issue on normal roads.
With the shocks anywhere north of that though, the ride is definitely stiff, not unbearable, but it's definitely noticeable. The GC's for the konis have higher springrates (350f/280r?) than the universal ground control (special edition) but that's because the koni's are valved for it. Also, the springs they use (eibach) have linear rates, so the ride quality isn't as good as say, a typical set of progressive aftermarket springs. But with linear rates you get better handling.
It really boils down to what you want, but out of the box GC's + Koni's is a great intermediate setup between casual street and occasional race.
Shingo