I bought a second hand racket and the strings that came with it were new pacific polyforce extreme strings strung at 60lbs. I tried it out and it felt good so when it broke, I went down to my local stringer and asked for the same string. Now the stringer told me he didnt carry the extreme strings and that it wasnt in the catalogue. He told me that my strings (the broken ones that were still in the frame) were pacific x force strings. Which is understandable cause the colour of the strings are the same imo. So my question is do they play the same? Should I just save the trouble of finding another stringer with the extreme and just string with the xforce since they are the same? Or not? Please advise me. Thanks a lot!