What's the main difference between the 910 D2 and the 913 D2...???

I'm considering replacing my 905R. I can save $100 by buying a new 910 as compared to the 913. I was just wondering if the 913 was that much better ?? Is the 913 that much better ?? 

Charles, I have both drivers, and for me the 913D2 may be slightly better than the 910D2, but not by much. It's definitely not $100 better. Save your 100 bucks, and put it towards a Scotty putter or Vokey wedge.

Main difference is that the 913 has like 15% faster ball speeds and like 300-400 less spin. I gained about 10-15 yards with the switch, I miss it straighter also. In my opinion the 913 is better than the 910

The downside is the shaft selection for a 910.  The models are the leftover/off the rack models.  Even for $300, I'd want to go through a fitting for the correct shaft/head combination for me.  You may want to try the 910 compared to a 913 to be sure.

To note I picked up a used 910 and will be keeping it for now.  It was already an improvement over my last driver.