ok, so I just demoed the v8 18x20. I demoed it alongside my v7 18x20 and the gravity pro. I think my review will be quite a contrast to the previous few on the last few pages of this thread, but nevertheless, here it is.
The V8 18x20 was a complete disappointment and was easily my least favourite racket of the session. It was strung lower than my v7 18x20 but I felt like it had LESS power, and it definitely was not as precise. In fact, it was easier for me to switch from my v7 to the gravity pro, than it was to the v8!!! The gravity pro was what surprised me the most. It's a completely different racket from the tour and mp (both of which I tried and disliked).
The gravity pro was also strung a little lower than my v7, and it had more power. Serves definitely felt more powerful, and groundstrokes too. Only thing it was missing was the precision of the V7. I was playing match tie-breaks with my friends, and I found that when I was under pressure, I needed to switch back from the gravity to the v7, because the V7 just paints those lines and gives me the amazing angles and control (however maybe this is because the gravity pro was strung lower, but then again if it was strung higher, it wouldn't have felt so nice power wise!).
I mean, I really wanted to get a 2nd V7 18x20 with a matched spec, but all in my size are sold out in Europe, so I am looking for a replacement to keep my V7 as a backup, especially as I plan on getting back into tournaments. I was hoping V8 would be an easy choice, but so far it has disappointed a lot! Gravity Pro seems to be first in line (although at this point I still like my V7 more).
Strings were Alu Power roland garros for v8 18x20, hyper-g 1.15 for v7 18x20 (23/22 kg but has loosened up since playing. I checked this with a friend who was freshly strung with 23/22 and my v7 definitely lost some tension when we compared). Not sure about the strings on the gravity pro.
Power: GPRO > v7 => v8
Precision: v7 > v8 = GPRO
Manouverability: v8 > GPRO=v7
Serve: GPRO > v7 = v8
Control: v7 > v8 = GPRO
Groundstrokes: v7 > GPRO > v8
I intend to play again a few times more this week and will update if things change! But yeah, quite disappointed