Airsoft & Milsim News Blog covers the Delta AK-21 AEG from Nuprol for the latest review... "The Nuprol Delta AK-21 is an interesting and, at current, unique AR style AEG. The externals are good, and firing feels crisp and closes on authentic. Sadly, the gun is plagued by a number of quality control issues and low power out of the box. Magazine compatibility also leaves something to be hoped for, and the replica’s exterior design does not match the original on the lower receiver.