After talking to Jim at the Tire Rack, I decided to try out some Avon Tech M500's on my S2k. After about 2 months of daily driving, 1 autocross, and 1 track day; I love them! They seem to wear a bit quickly, but no quicker than Falken Azenis ST-615's or Hankook R-S2's.
Grip-wise, they hold fantastic. Just about as much lateral grip as the R-S2's, but less sidewall flex (which is a defenite plus if you want to hit some turns). They also only ran about $100 per tire for 16's. I think the 245/45 was $107 and the front 205/50 was $95 each if memory serves. Wet weather traction is great, but if you try and push it hard through a turn, they'll kick out on you. I think they also make them in sizes for an MSP.
The R-S2 is also a good, affordable tire. It's a little more predictable than the M500's for a less experienced driver. However, both tires are a no-go when it comes to snow. Whatever you do, avoid the Hankook HRII. I ran it on my MSP for a few months, and I hated them. Terrible traction in wet and dry, and the wore out far too quickly or as little grip as the bore.
