The MP 38 and MP 40 (MP designates Maschinenpistole.), often wrongly called Schmeisser were submachine guns developed in Nazi Germany and used extensively by Fallschirmjäger, tank crews, platoon and squad leaders, and other troops during World War II.
Replacing the was a gigantic waste of money and a step backwards in my opinion. There is something to be said about belt fed capability and also having the ability to accept standard 30 round magazines. Not to mention the quick change barrel.