I've got to say that on paper, I really like what the XCR has to offer.
Quite honestly: The lack of major military testing/usage to improve the design is what scares me about it. Seems like without the backing/financing/support/development dollars of a major military, you end up with rifles that are great in concept, but poor in execution. Example: M96, etc, etc, etc.
These piston ARs (yeah, I know the XCR isn't an AR) are all the rage these days, and everyone likes to talk about their reliability on the internet, but to the man, everyone I have spoken with who saw one used in an intensive carbine class said the new piston uppers were considerably more apt to fail than the time proven modern DI uppers. Why? The answer is that they don't have 45 years of R&D and worldwide military use behind them. When they do, maybe then they can match or exceed a classic AR, at least in terms of reliability.
That said, I'll still be following the XCR reports closely. The "new" rifle that really intrigues me the most is the FN SCAR entry. I believe that platform has been through exhaustive military trials in its current form, is based on the old FNC, and if it is introduced to the market in a true milspec-minus-the-happyswitch form, I believe I would buy with confidence. The Sig 556 may also fall into this category, depending on how much the upper shares with the European military 550 uppers. This is also yet to be seen, but time will tell.
We were the 2nd largest Robarm dealer in the country, but that was before the Veprs quit coming in.