I have the Yonex Isometric 75 MF light still in the factory strings. It is my back-up racket and the racket that my parents (beginners) use. I would like to string it, but the recommended tension for the racket is 15-20lbs. I was wondering if I should just string the racket at 20lbs or a higher tension? Is stringing at 20lbs "worth it" because it's sort of low? My main goal is to improve the feel of the racket without risking its durability. Please advise. Thanks in advance. Edit: My current racket is strung at 22lbs with BG85.