as tempted by PeteLSD, i attempted stringing a Panda Ultra Pro at 44x46 today. he suggested starting lower but i thought, what the heck, no guts no glory. as you probably have guess, by attempted, means that it failed. i used BG65, tried ZM70 new earlier but they snapped in the first few mains. i don't think the new ZM70 are suitable for such high tensions. anyway, it was successful for the mains, did flat 44lbs throughout the racket, no proportional. i finished it and tied off. the Ultra Pro is very impressive, some deformations but the frame is rock solid considering how much force was on that thing. i tied a couple of dummy cross strings at around 9 and 11 o'clock to secure the frame. that's went ok. and then i started weaving the cross, bottoms up. 46lbs. everything was ok until around the 5th cross from bottom. the main string snapped at the top. the grommet hole that broke it forces the string at an angle and thus created too much stress. the Ultra Pro on the other hand, survived and lived to see another day. the weakness at this tension is the string. if we can find something a bit stronger than BG65, this maybe a success.