I've heard many different opinions on tire life. How long should tires be on a car before they become unsafe? Do they deteriorate from the inside? I know a fellow with a Testarossa (first year of production) and he's proud of the fact that it still has the original tires - TRX as I recall. I'm not sure but I think it has less than 10,000 miles. He rarely drives the car but when he does, he really drives it hard. Is he living on borrowed time? I'm no tire expert but I'm sure a few of you are. So, let's hear some opinions and/or facts.