These AR-15 .22's are becoming all the rage. I need another rimfire like I need a hole in my head, but I'm tempted. So far the one to beat seems to be the Colt, Umarex M-4. It has all metal construction, and emulates the full size gun very well. All seem to run in the same price range. I haven't read any "tests" on them so I'm not sure about function, but for the price, along with the amount of them they are selling, I would not have a problem with taking a chance on one. With the cost of .223 remaining high, these will only get more popular. Bill T.