300 miles?! geez....then i'd almost have to buy a new pair every 6-7 weeks!!

i guess that's why they say you should also always use at least 2 pairs at the same time and alternate. i think you can get a little more mileage out of them that way. the other benefit is that your feet are supported slightly differently. this trains the muscles in the feet, making them stronger and less prone to injury.

oh man...i think i need a new pair after reading this thread! i'll wait 3 more weeks and get a pair at the expo at the marathon i'll be running...