I was fit at a Titleist Fitting Center for AP2's and my 6 iron numbers with the DG X100 shaft are below:

Ball Speed 130

Launch  17*

Spin  6200

I have a friend who asked if I hit the KBS C Taper and when I told him that I did not he said that I was missing out.  I went to the Titleist iron shaft matrix and it looks like DG and KBS C Taper are right next to each other and the specs look very similar.  

So my questions are regarding the difference (if any) that I would be gaining from the DG X100 that I was fit with versus the KBS C Taper?  Is it worth the up-charge since they are so close to eachother in the iron shaft matrix? 

Thanks in advance for the feedback!