When I tried to demo the cortex version of the APD just when it came out ~2 yrs ago, I immediately returned after playing just an hour. I didnt buy the cortex and personaly thought it was a nice marketing ploy. Now that I am planning to add more spare rackets (and replace the worst condition non-cortex apd), i noticed the **** sellers are really trying to sell this supposedly older technology as if they were brand new or even higher than their original retail price! Are these sellers just plain greedy or these rackets (non-cortex apd) are just great? p.s. yes Im aware nadal is still playing with the non-cortex version.