SO, I caved and went with Ruger's SR556. I know, I know, there's going to be a lot of people for and against the DI system vs. the gas piston, I know I know, there may be other DI systems out there for the same price that may be proven AR's, I know, I know there are going to be SCAR's and ACR's and so on and so on...but I WANTED the SR556. I will be offering up a range report and over time a longevity report. I have had great customer service and response from Ruger regarding my questions to them about the piston system and the "carrier tilt" issues I found during research and they replied in timely manners with solutions and the porduct guarantee of if there product has issues they will address any problems. So the AR is on the way as we speak. I've never wanted to see a Fed-Ex man in a purely plutonic way so much in my life.