I don't know why some people poo poo on RRAs.
The reason is that some cowboy over on m4carbine.net put together a "comparison" chart. In the chart, he listed all the features and their specifications. The "standard" was the Colt offering. The closer a product came to the Colt specification, the more "points" the product was awarded. There was no provision for comparison of the specification to determine which one was superior. Consequently, according to that chart, RRA and a lot of other top quality ARs come up short.
But the proof is in the pudding. In the marketplace, RRA has proven to be accurate and reliable. Personally, I find even military specifications can be suspect. Just because some piece of equipment meets some arbitrarily defined military standard does not mean that it is the best, best for the money, or even reliable. It just means that the equipment meets a standard that was set by a bureaucracy.
If you ever read the story about how the DOJ came up with it's body armor rating system, you won't worry about DOJ ratings.