I've seen several XCRs need work out of the box to prevent then from jamming all over the place. Yeah, it would result in a pricey gun, but look at what ATR is doing. The bolt/extension, and gas are all robarm. They are changing a barrel. Does that come with a bunch of risk?
Unless I read the OP wrong, the cost here is an XCR+550, not 1500+2500. The latter gives you 2 uppers. no?
You forgot you need to buy the 7.62 kit which is 750-800 dollars plus tax plus shipping.




















































