I would say set up a fitting with a qualified Titleist fitter (check Titleist Thursdays to see if you can find a session in your area) , take your 913 with and then you can compare your 913 head-to-head with the 917, so you see which gives you the best performance. Your 913 is two generations old already and the technology in the 917 and it's performance may just knock you out.

I too have the Titleist 913 D2 Mitsubishi Rayon Blue S+ 60g. I have had this club in the bag for about two years now and love it. However, I got the chance to demo the 917 D2 and there is no doubt in my mind that I will the switching. The feel for me was better, the distance was longer and I was more accurate. I demoed the D2 with the Mitsubishi Rayon Blue S+ Limited Edition shaft that has the new pitch fiber material. The ball just flew off the face. I know you love your 913, but go and demo that 917 before thinking about reshafting options.

Can't wait to demo the 917, it's sure to be a better product than the 913. Just try like for like and see/feel the difference.

Quite expensive compared to previous models, about £100 more on both driver and fairway, thank goodness my wife doesn't subscribe here

I find the 910 drivers were one of the best Titleist came out with. I had the 913 and now the 915 but just don't love the feel of those as much. I may try the 917 over the winter. Anybody else like the old 910s and can make a comparison to the 917s?