Look at the new Pirelli P Zero's for ultimate street performance. I just got them and they rock!!! Performance wise they are ahead of the PS2s. Crisper turn-in, more grip.
In TireRack's latest tests, they beat out the PS2 as well.
if you want EXTREME performance, go look at the new Bridgestone Potenza RE-11's, That was my 1st choice but they are not available in the sizes I need yet on my HRE wheels, but I will probably go with them when the PZeros wear out, as I am sure they will expand the sizes by then. Just remember the treadwear rating on them is 180, not the 220 like the PZeros or the PS2s.
11' Cyber Gray Corvette Grand Sport
08' M3 Interlagos Blue: 6sp, Tech. & Premium Package
07' 335i E90: KWV2, H&R Sways, SSTT
01' & 04' Corvette Z06