I will add my .02 cents.
I just removed Mazdaspeed PRHT springs & NC2 Bilsteins from my wife's 08 (NC1) GT, soft-top. I installed a set of NC2 front springs, Koni's w/ a set of low to mild sway-bars. I like the RX-8 red front w/ yellow rear, they just work very well for a DD & are well balanced at the limit.
I will say I was totally shocked
on what just Koni's & sway-bars do for this car. It's not going to the track or autocross, it's just my wife's DD. Remember we are in our mid 50's so this is coming from someone thats over the hill. (I am not my wife.
My word of *advice* is buy Koni shocks.