Finally installed RaquetTune on my iPhone and iPad and measured tensions of string beds on 3 identical Head Prestige's, all with Babolat BT7 guts. #1: measured 52# (requested 59/60# a few month ago, played a few weeks). #2: measured 56# (requested 58# 2 weeks ago, have been playing since then) #3: measured 66# (requested 62# 6-7 month ago, played only once) I know these are only reference tensions but #3 clearly was a bad one, I concluded. I requested 62# but I think the stringer( person or machine ) probably pulled it at 70+ lbs. It felt dead and I stopped playing with it. BT7 with this high tension is probably unusable. There goes $43(string) + $22(stringing fee) wasted.