Hello, I've been gaming a 915D2 w/ Rogue 110 70X since the driver came out and been pretty happy. I've hit it pretty straight in general but the club always felt a little spinny to me and never seemed to run out very much.

I recently got on a launch monitor with my driver and my spin was very high (all 3500RPM+) and the smash factor and ball speed were all less than ideal. I hit some other manufacturers clubs and ball speed and spin were dramatically better than my 915D2. I ended up buying a cally 816 Double Black Diamond, but since I've had that driver I've had real trouble hitting it straight and keeping it in play. I am a Titleist loyalist so putting another manufacturer in play was very hard for me to do.

I've since put my 915D2 back in play and hit it straighter again.

So my question is, all else being equal (loft, shaft, consistency of strike, etc.) how much less would a D3 & D4 spin as compared to the D2? It will be very difficult for me to get my hands on a D4 without buying one and trying it so I need to do all the research I can. I played a 910D3 and hit it really well in the past, the only reason i went to D2 was because I thought I read that the spin difference in the two heads (D2 vs. D3) was negligible so I opted for 460cc and more forgiveness.

I'd like to drop 1000ish RPM and get the smash factor back up to where it needs to be to maximize distance while keeping the same familiarity with Titleist heads.

Thanks in advance.