Attached is a summary of the actual tire tests (not owner surveys) posted on Tire Rack that relate directly to the RX-8. As part of looking for Potenza replacements, I researched 225/45R18 "summer" tires and 225/45R18 or 245/40R18 Ultra High Performance All Season tires. I compiled the track testing results where they used the same basic test car, wheel size and tire width. While not perfect, it at least give you the ability to do a ballpark comparison.

Note that some tires had a the testing setup that was substantially different, so I did not include them in the summary as I was not confident a valid comparison could be made. Also a number of tires had no track test data. So if your favorite tire isn't listed it doesn't mean that its not a good tire, I just didn't have the data.

I figured being that I did the work, I might as well share the results, even if all it shows is that, in general, Summer tires perform better than All Season tires in dry conditions. I included JPGs for easy display and a PDF if you want a printout.

FWIW