Finally went for a proper GTS Fitting at a Titleist Demo day last week. I had benched the GT4 and gone back to the TSR3. Some key takeaways: - As much as I want to think that there's no noticeable improvements from gen to gen, the data couldn't be ignored, I swung GTS4 faster than my TSR3 (same shaft) - There was a discernable 2 MPH ball speed gain and about 6 yards overall. I did hit more than 20 balls with each. - The sound of GTS is way more "thuddy" or "carbony" than any Titleist I've ever hit. I hated it at first, but came to not notice it before too long - GTS4 was a little better out of the heel and low face, and about the same out of the toe for me. - Gonna be an unpopular opinion here, but the price is insane. $980. I have to order a shaft with it, no "head only" option as usual. I've already been fitted into and purchased a $550 shaft that works perfectly in the new head. The free shafts that come with that $980 driver aren't worth $90 on eBay.

Another great driver from Titleist, but I'm not paying $980 for one. It's good, but it ain't that good.