My humble advice to anyone else, with stock F1s on a GXP/Redline:
(I have been daily driving mine since 2008)
Ditch the F1s asap. I pulled them off my wife's car after the first year and replaced with Eagle GT Asymmetric. She drives in blood alley between Ft. Collins and Denver on a regular basis. (Looking back, I wish I would have pulled them in the first month) The F1s are an ok dry/warm weather tire. But quite frankly, they are not even great in those conditions. For a supposed "High Performance Summer Tire", my stupid old school BF TAs stuck better. And the rain groves on the F1s are very minimal. Fine for light rain, but as soon as you hit anything moderate to heavy, they just can not channel enough to do much good.
The GTs are far superior rain tires. And, they are stickier in dry/warm conditions than the stock F1s; which is amazing because you actually have less foot print because of the wider rain groves. But the rubber is gooier. The tread is waaay deeper, so very good water channeling abilities.
I burnt though the stock F1s on my car in about 30,000 miles of road time (summer only, I run snows in the winter). And after about 15,000-20,000 miles of road time; they became very unreliable in rain conditions. Hydroplane City. But I was aware of it, and took precautions. Besides, I am a cheap bastard, and like to get my money's worth.
Now I am burning through my wife's left over F1s that I pulled off her car. I figure I have to more seasons, before they are down to cheater slicks as well. After that, I will finally get something decent for my car.
Believe me when I say, tires make all the difference in the world on these cars. My wife's Sky is completely stock, not even a tune. If I am following her through the twisties, she can walk on me like I am sitting still. My 80 lbs of torque advantage doesn't mean jack crap when she can stick like glue.
And if we both leave from Loveland to drive home to Ft. Collins in the rain at the same time, I get home 30 minutes later.