A recent golf magazine "test" showed that lighter is not always faster - the original theory behind the 44g shaft and under 300 g driver. So it really does come down to personal preference/performance. Flex and torque are also part of the equation. The 917 is so darn forgiving, I prefer a lighter shaft to keep from "getting stuck". On irons, I prefer a heavier weight to control tempo for consistency. ...Your results may vary.. Definitely try before buying.

I can't speak for a driver, as I am in the process of putting a new shaft in mine now. As far as fairways go, I prefer a heavier shaft. I actually picked up some swing speed using a heavier shaft (Fujikura Speeder TS 84) than a 70g Rogue in my 917 F2. It feels great.

I also play with a 74g shaft in my driver, more for stability then anything else. I have tried both lighter and heavier shafts (even of the same model with similar torque and flex) and this is where I fell more from a feel perspective than anything else. As far as performance is concerned, I had very similar swing speeds with a little variation in the spin rate from going up and down in weight on the same shafts so I settled based on feel. I would recommend getting on a launch monitor so you can really see if there is a benefit from going lighter.

A lot are based on swing speed and obviously everyone is different, personally I prefer a heavier shaft , it helps me hit the ball straighter , but my mate has a similar swing speed and he prefers the lighter , because he gets more whip , it's just personal choice I'd say !!