they get loose as a goose when over cooked. i've only overcooked mine once. it was at the end of a 20 minute road course at lowes motor speedway.

as for lasting a long time....i've had mine for exactly one year and one month. i've got about 22,000 miles on the tires. the rear wore out last month, the fronts are at half life maybe more. i dont rotate tires either.