Definitely go with TSR fairways. I have the TSR3 driver with Tensei Blue shaft and have basically the same shafts (slightly heavier weight) in my 3 and 5 TSi1 fairways and my TSR1 hybrid. Fit for TSR1 fairways but just have not got them past by live-in budget monitor yet.

The more I research the more I think that will be my plan. This may be a fall/winter project. Until I got the TSR3 driver I had never really been willing to spring for premium shafts because I had in my head they were a cash grab. I have changed my tune and am now 100% on board. I am working hard to get better now that kids are older and I have the time I will be playing a lot more. Also, my daughter is learning to play. She is a 14 y/o elite travel hockey player and is getting really good really fast so I need to step my game up....lol. I appreciate the community here and look forward to responses.

Graphite Design shafts are the bomb!!!! Yes they are pricey but golf in general is pricey.
I'm 66 years old and always tinkering looking for a few lost yards. Had a quiver of shafts for my driver and fairway, but settled with the AD-VR5 shaft in my TS2 driver and the AD-VR6 in my 3 wood, and they were great. Similar to the AD-IZ but a little lower flight for me. Had a driver fitting and the guy told me that if I go to a 6 in my driver it tightened up my left to right dispersion. Decided not to get the new driver but last year I traded in a bunch of shafts and went to the AD-XC6 in my driver and it's a pretty mean stick. A little lower flight, less spin, a few extra yards, and better control. Now carrying the XC6 in my driver, the VR6 in the fairway, and the DI in my hybrid, and not interested in changing anytime soon.

You could be surprised at the fitting how well the stock shafts perform and save you some cash!

TSR3 driver with Hazardous Black and added TSR3 16.5 fairway (replaces 3 & 5 woods) with same shaft, but heavier. Works for me. I recommend getting fitted and using whatever you hit best.

Update: Titleist has announced a fitting event at a club a mile from my house so I snagged a time to get fit for fairways. Will report back.

If it works for you then go with it. I did a fitting event for a 3 wood and wound up with the TSR2 with the Hzrds Black 4g 70g 6.5. I have never played xstiff but that shaft was great in the fitting. I avoided my previous 3 wood for years but now it’s a weapon. It was one of the stock options with no up charge. Titleist has many great stock options. But if an up charge shaft works then do it. The additional $$ is well worth the investment.

The TSR line is excellent.