for what it's worth, we're about to replace the original Toyo Proxes at 29K. They're just now approaching to the wear bars but they're sliding in a moderate rain and we don't feel safe driving on them any longer. The thing that surprised me was that the treadwear warranty on a couple of competitors I looked at was around 30K, I can't remember if it was the Goodyear Eagle RS-A or the Pirelli P6 Four Seasons, but the other one wasn't much higher. Definitely the shortest treadwear warranty of any class of tires I'm used to buying. In any case, we decided on the Michelin Pilot Exalto A/S, which has a 6 year/45K warranty. We'll see what happens.