Reviewed last month by Hyperdouraku is the S&T Beretta M12S AEG. This has a metal upper receiver with realistic markings, metal muzzle, metal sights, and metal side folding stock. The Polymer part is the receiver grip whilst the 50-round magazine has a steel housing. The foregrip can store a 7.4v Lipo battery and also comes with a sling mount.
Read the full review here (in Japanese).