If you won't be able to take advantage of the faster lock time then I'd just go with a quality M16 BCG like BCMs. It'll be cheaper and probably better overall. Since you have a BCM already why not try that BCG temporarily and see how it works. I'd skip the "cool" factor, just buy quality that truly works for you.
And by the way the heavier carrier should be smoother than a lightweight. Also longer lock time is a good thing, it's only milliseconds anyway.
The biggest issue with assembling an AR isn't so much getting the parts together right - it's getting the right parts together. You'll remember the quality of a gun long after you forget how much you paid for it.
US Army 1966-69, VFW Life Member, Retired Geek
Last edited by Quentin; 09-28-2012 at 12:30 AM.