Stance makes amazing coilover and suspension systems. While they are popular amongst the hellaflush/stance crowd, there are numerous people in all forms of motor sports who are running Stance products and getting consistent podium finishes.
Not too sure about grip and time attack but my close friend, Forrest Wang runs Stance XR and Stance 3 way coil overs on his cars. He's finished 1st in every event he's participated in this season besides one (which he took 2nd place)
When I pick up my FR-S next year, the day it gets home, I will be making the call to pick up some Stance coilovers.