My suggestion would be to do a free Titleist Thursday fitting and see how much moving to the TS line helps. I know there is a significant cost difference between the older 917's and the current TS's but the technology is way better. You should at least consider trying them. Besides your putter, the driver is likely your most used club and the right one will keep the game much more enjoyable.

If you’ve had the regular before and haven’t had any issues then I would stick with that. It’s a known quantity. Ultimately I would go for a fitting though. Titleist Thursday’s are a great option to ensure you’re getting the best for your swing and game.

Take a little time and find a Titleist Thursday. Get fitted for your driver, you might find at your swing speed that a TS1 gives you a bit more distance and better shot dispersion. This will also help get you into the perfect shaft for your swing.

I also agree that a fitting is the best path. Empirically if R is not stiff enough, the head may over torque through the ball, resulting in some pulls. If the S is too low torque you may get fades. So how you load the shaft will dictate the shaft. How you swing will be individual to you. Our suggestions are no better than what you would guess.
Even though my swing speed is lower than yours, I ended up with stiff blue in a 917. I do agree that a fitting with a TS driver may be valuable. I gained 3mph club head speed and 2 more mph ball speed with a TS1 and no loss of dispersion

Hopefully this helps you and my english isnt too bad to explain this :)

I played last 2 years with 917 and shaft was same diamand regural shaft as yours and my clubspeed is normaly around 94mph and hcp 13.

Last december i fitted new ts driver and my fitter said that we go with 50g stiff. After 8 months of pushing and fighting i returned back to regular shaft.

Stiff was too much for me and i i had lot of problems with it. Last months i played with 3wood more than driver.

Someone suggested that TS1 and shops said to me that my club speed is too much because that driver is for avarage 220 drives or less. Also club speed should be 90mph or less...

For what it's worth, I have a similar swing speed. I played a Rogue Black Regular flex in my 915D2 a couple years ago. When I got fit for my 917, I was told I did better with the Diamana Blueboard 60 in Stiff flex. I didn't actually believe it, so later that week I picked up a used Diamana Stiff shaft and went out and hit about 20 drives off the first tee at my club when no one was around, with my 915.

I hit the first group of 5 with the Black Rogue Reg, then 5 more with the Diamana. The balls were marked so I could tell which was hit with which shaft. I hit a bunch of them very well, from both shafts. I did not measure the 2 or 3 less-than perfect shots. However, from the first group of 10, when I drove out to them all, I found the best shots were hit with the stiff shaft. Sometimes as much as 5-7 yards longer. The good shots with the Diamana stiff were ALL longer than the shots with the Rogue reg shaft. It surprised me, because I felt like the feel of the Rogue was better.

I drove back to the tee and re-did the same exercise, with virtually the same result from the next two groups of 5. I was sold.

Personally, I am not a fan of launch monitors. I like real-world WYSIWYG tests. I put the stiff Diamana 60 in my driver, then bought a 917 a short time later with that same shaft. When I moved to a TS2, I went with a Tensei Blue 55 stiff in it.

As an aside, I recently tried my old Rogue Black R flex shaft in my TS2, just for the heck of it. It felt great. I thought I might play it for a little while. I played a round or two, with great results, but decided I should change the grip. It was due. I tried an MCC+4 midsize for the first time after always using the regular MCC midsize on everything. That was a mistake. I hated the +4 in the driver. Couldn't keep the ball straight. Immediately went back to my Tensei with regular midsize and the ball straightened right back out!

Camp, going back to a regular shaft maybe the answer. I too have similar swing speeds and actually went to a Club Champion fitting. And they recommended and I ordered a FUJIKURA regular shaft on my Titleist 917D2 and I installed a Golf Pride Mid-Size grip and had immediate improvements in accuracy off the tee. 2 rounds I actually had 28 for 28 fairways..