Just received the TT Warrior over the weekend. Played with it, and it was good. 1. It came strung. Apparently, the smallest grip size (4-1/4) comes prestrung, and the other grip size are not strung. Why? 2. Should I change the string (from the string from the manufacture that just had the "Prince" word on the string). If so, which string should I change it to? Thanks.