Back in high school I always took back the pair of shoes and got the (1) free pair. 6 month shoes back then lasted me between 45-60 days. I was playing 7 days a week, usually 3-4 hours per day, it was the life. And oh yeah, no injuries back then.
Now I always forget to send my shoes back in, I actually kept the receipt this time. They are about 3 months old and wearing down bad. I guess with the New Balance they will not let you take them back to the store anymore, they want them sent in.
I willl be a very happy man when they figure out how to get a tennis shoe to be comfortable and last a loooooooong time without having to play on clay or grass.