Hisenberg, I'm with bcredliner & Bigblack on the logic, and can see buying two someone is swapping off their vehicle and selling on ebay or craigslist, especially if you have the 'staggered' wheel set on your X5 and can match at least type tire to the fronts you are keeping [e.g., asymmetrical summer performance, not mixing such tires with all season, etc.]; especially if the wear is close. That said, I'd limit my time investment in searching for/looking at used tires
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