I've tried many, many shafts with different drivers and have finally come to the conclusion that this is the best shaft for my swing.
I have a 95 to 100 mph swing speed and hit the ball fairly high. This shaft in regular flex gives me the ball flight that I'm looking for. I can turn a driver over with this shaft fairly easily when I cannot with some stiff flex shafts.
I've tried most pro line clubs with stock shafts and other shafts such as V2's (felt dead), Aldila VS Proto (ballooned), several different Fujikura shafts (too soft), and several different Graphite Design (no distance) shafts. None of which worked nearly as well as the NV65 for me.
I recently purchased a 9.5 Ping G10 with their stock shaft in stiff flex after being "fitted". Same ol' same ol'... Ballooned drives with a weak fade. Reshafted it with a NV65 reg... and presto, I now have the driver I've been searching for. Prior to the G10 the best driver I've hit was a Tour Edge Exotics in 9 deg with the NV65.