Hi you experts. Last week I had a chance to buy 2 nikes (1 cage, 1 Vapor) real cheap. The thing is I got already an Air MaxII in very good shape, so I am wondering I will start using the first new one in 6 months and the other... who knows. So my question is: unused new shoes will have the durability dimmed? In what way? Does the sole go cracked or something? Tx.