Hi, I notice that generally the 2U Yonex racquets have recommended tensions that are generally higher than the 3U. Is this because the frame is heavier? Eg. Yonex MP-100 3U Main: 16-18 lbs. (7-8 kg) Cross: 18-20 lbs. (8-9 kg) 2U Main: 18-20 lbs. (8-9 kg) Cross: 20-22 lbs. (9-10 kg) I also noticed that the Titanium series such as the Ti-7 and Ti-5 Light have quite low recommended tensions: Ti-7: Main: 16-18 lbs. (7-8 kg) Cross: 18-20 lbs. (8-9 kg) Ti-5: Main: 14lbs -16lbs Cross: 16-18lbs Would it be safe to string the Ti-5 or T-7 at 21-22lbs? Does anyone have any of these raquets and would like to share their experience?