Current I am using 915 D4. The reason I am still on this driver was because Titleist did not make one in 917 series. I did try 917 D3 and D2, but it is not the same. It looks like it will be the same in TS series. That was the only driver I can get some distance on my drive. I had only my left arm function normally due to a car accident 13 years ago. Unfortunately, I generate a lot of spin in my driver, but with very low club head speed. As a result the ball climbs very high and does not go far. 914 D4 was the only driver I can hit with some distance. I tried all others manufacture low spin drivers, but most of them were worst than my D4. I am treating my driver like a baby, because I know I cannot replace it any more. It is shame.