fotosoup, judging by your "...shut up they were on the car when I bought it..." it sounds like you don't like the coopers...but why? I've never heard of them and couldn't find any reviews on them. I'd venture a guess they're H-Rated, but I can't tell if they're an 60,000 mile tire or a High Performance Summer tire just by the name, but maybe I'm horribly uneducated when it comes to tires.
I've put two sets of tires on my car since I've owned it. The first set, the Sumitomo HTR-Zs, had a Treadwear Indicator of like 200-220, but it seemed that they lost their grippy edge after about 15k miles. The next set, the Kumho Ecsta 712s lasted longer, but they've really hardened up since about the 25k mile mark.
I didn't know of Sumitomo until I bought my HTR-Zs (in the stock size), which I thought were pretty good--provided good grip and were quiet, but they didn't last long. Irrelevant anyways, since Sumitomo ended production of the tire.
I also didn't know much of the Kumho brand until I got the Ecsta Supra 712s (also in stock size) which I feel have been excellent in the dry and the rain, and still have safe tread for driving in the rain after 35k miles, although they're pretty hard and noisy at this point.
In both cases, I don't think I paid more than 75-80 a tire installed and balanced. However, I know I'm not pushing anything close to 300hp at the wheels. I haven't dyno'd, but my mods are pretty basic. According to HKS's staged upgrade chart, I should be around 285 bhp.
I would also like to know what tires the higher-power guys prefer, but maybe with more feedback on the longevity of the tires--as in, did the tires live up to the treadwear indicator number? Sometimes it seems that number's a bit misleading, although I do realize it does depend heavily on how nicely you treat the tires. If I'm going to have to buy tires every 15k-25k because of excessive wear at higher than stock horsepower (as the parent here states an interest in tires suitable for 300 hp) that will influence how much I can spend each time at the tire shop.