Soo... I just received the X2 mast in the mail and had a session on it + 150 hax. First impressions it's definitely stiffer.
I measured the best I could with a dial caliper that doesn't quite reach the thickest part of the foil section:
Original: 15mm profile thickness, 117mm chord, 1648g
X2: 17mm profile thickness, 127mm chord, 1726g
Both masts are 32".
Going off the drag equation, and assuming the coefficient of drag is the same for both foil sections, the new X2 mast should have 13% more drag because drag is proportional to frontal area.
Hope this helps someone