Is there anyway you could tell me what tension you guys string these at? I am playing good with the demo I have and I do not want to buy a new one with a different tension. It's pretty frustrating when you have to keep getting it restrung. And yes I do plan on buying it from tennis warehouse so can you help me out? I am pretty sure you string them with NXT Max? Someone told me it was around 57lb, but can you confirm that?