I just went through a pair of shoes in six days. I'm currently using the prince vipor IV. I play heavily on both hard courts and clay (har-tru) courts. I was wondering if having a different pair of shoes for each surface would help to reduce wear. Do you guys have different pairs for different surfaces? if so, do you have two completely different models, or just two different pairs of the same model? At the rate I'm going, I'm wasting a lot of money on shoes, so any thoughts would be very welcome.