Hi! I've been playing with a 2011 Aero Pro and used the Cortex version also. Recently the 2011 Aero Pro gave me some unwanted vibrations at some times that hurt my elbow. So I am looking for a not so powerful string that is not excessively powerful for the new APD. I am considering using full Polyfibre TCS at 52, a string that I already used in the 2011 APD and felt prtetty good. In your case what string would you recommend for me? And, what strings are you planning to use with the 2013 APD?