FTR, AGX have combined bound and rebound damping adjustment, but they are definitely a top choice for street suspension, partly because of that. As was mentioned, underdamped sprigns bounce, over damped springs are jarring. But when you have underdamped springs that aren't very stiff to begin with (like the stock springs on AGX on my Miata) the ride is fine because the bounce frequency of each end of the car is still fairly low. Stiffer springs oscillate faster when underdamped, which is why Scott's JICs were utterly unbearable on the freeway.
Bottom line, a GC/AGX combo with proper rates will be very much what you're looking for.
