Jarrod,

If your looking for something similar to X-100's in the Project X line then I would recommend the 6.5's.  I've played X-100's my entire career and put the Project X 6.5's in a set of irons and found them to be similar in ball flight to the X-100's.  However I did go back to the X-100's as the feel was a little different than what I was used to with the Dynamic Gold's.  If your a high swing speed player, I think the 6.0's may be just a little soft for you.  Just my 2 cents.  Best of Luck!

The new irons should be out anytime between November of this year and march of next year. As for shafts, I have played both of the shafts in question and I finds the PX 6.5 to play slightly stiffer feeling than the X100 because they have a very very stiff butt section. They are also a different feel.  I had to change back to X100's because I was suffering with major golfers elbow and after switching back to X100's the majority of the pain has gone away. the X100's feel better to me. With that being said if you could find a set of Old PX Satin shafts they would be the way to go, much more consistent feel and flex.