Verminator,
My serious guns all have either Chrome lined or stainless barrels, 158 carpenter MPI bolts, and a BCM mod 3/4 charging handles.
I like a low power Leopold variable scope, good light and backup irons.
For a general purpose muzzle device, Iike the BCM mod 0, or the A2 birdcage if I'm on a budget.
I like the Wylde chamber, but have some 5.56 as well.
Extra parts are a good thing. If it's a spring, or under spring pressure, at some point, you will loose it, so have extra's.