Even though its only a few bucks difference a dozen, I'm not paying more for the same exact shaft. The tolerances of "The pro series shafts are graded for .001and w/i +/- 1g, where as the xt are graded at .003 and w/i +/- 2g" are max tolerances. At the very most thats what they will be off. If you buy a dozen XT's, there's not a doubt in my mind that the entire dozen could all be within the Pro tolerances. I don't shoot at x rings, so I think I'll stick with the XT's.