FYi ...GAB in JApan is longer exist for more then 3 years already, those which made from Japan GAB were from chopshop itself you can find...our Local GAB alreayd broguth over the license of GAB to build it here. so what ever it produce are all buatan malaysia...
RS one have test car for you to ride one...give you self a try on it.
Cusco, also a great branding for japan but now inorder to have lowe price and R&D for local street condition it now also have it on assembled in local if not mistaken same factory with GAB.... try search Hypertune for the past 2 years..already mention...yet they provide test ride for you as well...
go test yourself...you choose for your own...coz everyone got it own oppinion ..becoz is their own butt.
for my own use...i will choose GAB for my leisure family drive i mean in slow speed....less bumpy..but high speed slightly bumpy...for my another Set i will Choose HWL (mine was costumize) for my autocross setup...bumpy in slow speed...and less in high or full speed..
also to much with your suspension..1st you must really know your car chasis flexibility well...
all you can find online teaching how to do matching.
that my own opinion.