The H&R setup is generally garbage. The wildly progressive springs are all about slamming and looks, but the kit was stupidly designed such that the front lower perch and barrel spring intrudes on the tire and wheel if the car is lowered very far. This means the crazy spring rates that allow you to run super low with almost no jounce travel provide no benefit at all because the tire rubs the coilover assembly at that ride height. The kit also severely limits opportunities to run oversize wheels. It amazes me to see folks buy it and then resort to running big spacers to provide enough tire clearance to lower it with std OEM wheels.
Your best options are likely GC, PSS9 and KW. Each has it's own pros and cons for various applications. There is no best kit for all use.
1) GC is generally better for serious high performance street or track, plus it allows a bigger wheel/tire combo on the front for max grip & severe duty.
2) PSS9 & KW are generally better for slamming & regular street use, assuming you intend to stick with traction-limiting staggered wheel setup.