I have bolt carriers on a couple spare uppers done in chrome and the Bearcoat premium matte. There is no doubt to me cleanup for both is much easier and quicker than the standard one I have.
There may be accelerated wear with the chromed one. I can't tell I'm not an expert but at 5 thousand rounds the action is smoother and more friction free than standard one too.
I'm not to worried about accelerated wear using the Bearcoat. It's teflon...and some other things. I'm surprised by how well it's holding up but the upper it's on was Bearcoated too. Teflon on teflon.
I've never done the bolts themselves though and left them stock.
With regard to chrome flaking off the carrier... sure that would be a problem but if not if the chrome job was done right. I don't have any flaking yet at 5K. But what the future is for it I dun know. So far I'm quite happy with it and the AR has a cool look with the matte chrome showing when the ejection port door is open. I'm a sucker for a "cool" look. Geez.