I had a chance to try a fellow golfer's Graphite Design X5 shaft recently. I thought my existing Cobra had a great set up for me (70 years old, stiff, high 90's driver swing speed, 8 hcap). Typical drive 140 - 155 yds. I hit my driver and then his on holes 16 & 18 at Papago in PHX. His driver was 40 yards and 35 yards further (180 then 175!) WTH!!! Couldn't believe the shaft could make that big a difference.
Hope I get to evaluate this against my existing on a proper test.