Okay, got a response back from MT about tread wear. Short answer they gave me was that they are a specialty tire manufacturer and therefore don't publish UTQC data because most of their customer are more interested in traction than treadwear and temperature ratings. That actually kind makes sense because they make a lot of racing tires. They also asked that I call them for more info, which I did.
On the phone, they told me that the treadwear designations are actually a somewhat arbitrary number when comparing different manufacturers, but is very informative when comparing products from the same company. The reason being that there is no Federal standard for methodology for performing the testing. All manufacturers set up their own testing on their products lines and use a 100 rating as the base line. This baseline can be a tire that will last 10,000 miles or 50,000 miles, whatever they choose. From that point, every other tire in their line is evalauted against that baseline to determine the multiplier that determiens the rating. Therefore a 200 rated tire would last twice as long as the 100 rating, a 400 four times as long, etc. But, since the baseline can vary, it is possible to have 400 rated tires that last 20,000 miles or 60,000 miles. Although typically the higher rating is going to mean a harder tire which will trade off mileage for grip.
FWIW, they did say the S/Rs line typically averages 12-15 thousand miles worth of normal driving. Burnouts, autocross, and other spirited driving activities will make that number drop significantly. They have one customer who is up to 20k on them, but he does not use them for anything other than cruising. Since I've heard of BFG T/A tires getting 25-35k in average crusing, I'd say the S/Rs are a bit softer. How that will stack up against a Maxxis, I don't know.
