I got rid of the original equipment Goodyear Integrity tires after 6K miles, as we were heading to Lake Tahoe in December 2005 and I did not have confidence that those tires would do well in the snow. At that point the tread had worn about 40%.

I bought Bridgestone Dueler H/L Alenza (special ordered from Costco & the tires were inflated with nitrogen, Costco's normal practice). Those tires are great and I now have 21K miles on them. Extrapolating the tread wear, it looks like they will last about 50K miles.