Well I'm looking at some tires for my car and I'm unsure of what I'm looking at. School me on treadwear rating numbers. The current Michelin HydroEdge tires are at 6-7/32" of tread at 56-57k miles and are realllly loud on the highway. What I want in a tire is a high treadlife. I don't want a tire that's going to need to be replaced in 45-50k miles unless it's at a really good price. The tires I'm looking at have awesome rebates on DTD. Hankook Ventus V12 EVO2 Treadwear rating 320AA - Really not sure about these. This tread wear makes it sound like they'll wear out really fast. Yokohama Envigor Treadwear rating 560AA Cooper CS3 Touring Treadwear rating 540AB So are any of these halfway decent?