I purchased this set based only on others reviews(here and on other forums) and am happy with this set. Great tires and based on tread wear I find them almost unbelievable how good the traction/stickiness they provide. I was going to buy some with a much lower tread wear number to get high performance but based on the price and reviews I tried these and I'm happy I did. These plant my car very confidently into corners and grip the whole way through. My car can be difficult to drive but with these it's less difficult and rewarding every time I drive it. They also hold the power of my turbo 911 better as well. I'd recommend these tires to another Porsche 911 driver.