backinit I demoed the club from our Pro shop with the 65s. Seemed ok, but 65 is usually a driver shaft for me. I also demoed last year's 7w with 65R which also seemed ok.
Many times it seems like weight is 75% of the equation for me and flex is the other 25%. My swing speed is probably more R to Firm flex, but my quick tempo and hatred of missing left can bump me into Stiff π