I have both the Dragonfly J107 and GSII. While I can't comment on the X2 I can comment on EB packs themselves.
Outstanding! Well thought out. Functional, designed well, constantly improving their design. Lots of good accessories. I hunt with both my packs, carrying my rifle in their internal scabbards. I've gone in "light" and come out "heavy" just as their advertising states, carrying lots of elk meat out.
This past Fall I trusted my J107 to carry my extremely custom Pre 64 M70 in 257 Rob.
I had one mishap with my J107. I was headed up to Alaska in Sept 2008 on a Grizzly hunt and my pack was my carry-on luggage so it was packed very heavy with my clothes, optics, emergency gear, etc. Went to lift the pack up on my back via the carry handle on top and it gave way. Upon return home I contacted Glen EB and he had me mail it to "his house" with pre-paid UPS shipping. He personally repaired it for free and sent it back to me. That's awesome CS.
Alan