After researching, reading reviews, and procrastinating for a while I decided to go with the Ruger AR-556. Got it ordered this morning along with a few 30 round PMAGs, a Magpul MOE M-LOK handguard, 500 rounds of .223, and 120 rounds of 5.56 ammo. Any issues to worry about besides the threaded Delta ring issue? I will put anti-seize on the threads and avoid over tightning when I replace the handguard. Now just waiting on UPS, FedEx, and a phone call from the FFL.