My current favorite is Hankook R-S4 285/35/18 square. 200u $1090 set Tirerack + shipping - they love the heat and wear very well. Not as fast as RE-71's but close. Very good in rain. Better than the R-S3 which I believe is still available in some sizes?
Look at Michelin Pilot Super Sport same size. 300u $1057 set Tirerack + shipping - superb in dry and wet but tend to delaminate at the wear bars. You might consider having these shaved?
Bargain basement great wearing sticky tire but you're not going to win anything. Sumitomo same size HTRZ II. 360u (they used to be 200u but they remarked them) $650 set. Consider shaving them for $25 each since they are so affordable. Great rain tire and stick very well in the dry.
Personally I have two sets of wheels and mounted tires. One stock size for reg C5 (cheaper) and one set aftermarket 10.5"x18" with toyo 295/30 R888R's on them. I would have preferred the 305/35/18 R888 Toyo but they were on back order at the time.
All are available thru Tire Rack and others. No clinkers in the bunch. If you could wait they constantly have rebates on tires up to $100 a set.
Why the rush? Deals are to be had.