Yep I've got the RS Chip. Considering the GTS but at the same time there's always an element of risk involved. I think the RS just worked better for me in terms of value (almost half the price of the GTS down under).If you drag race, then I would say go for it. My friend had a VW Golf R, he would complete 11.5 index class. He would be a tick behind because the Golf 4 has a bit of delay from mashing the pedal to when the car reacts. He would lose races that way since it was heads with a .400 Pro Tree.
Otherwise like I said you likely won't need it and a more touchy pedal might lead to more wheel spin. Spinning isn't winning.
Spot on, right now, if I foot down the pedal, the car wheel spins quite hard (I can't remember wheel spinning without the racechip?). So I would need to accelerate quite gently to avoid the wheelspin already. The pedal box would be used to change the sensitivity of putting the foot down on the accelerator and I can't see it really helping that much...