The Nylon Fiber + Aluminium Alloy AEGs from Ares Airsoft, and definitely affordable are in stock at RedWolf Airsoft... "Ok, so ARES have made another M4 but they are always doing their best to make the replica the best one yet! This is the new updated version so it's made out of an Aluminium alloy and Nylon Fibre, still, attention to detail has been paid to things such as the bolt locking/bolt catch which is fully functional. The build quality is rather solid and has a good weight to it. A very good choice if you fancy having an M4 in your arsenal. It has a 300 round magazine and fires a decent 380fps on average."

ARES M4A1 Nylon Fiber+ Al.Alloy Version - BK

ARES M4 CQC Nylon Fiber+ Al.Alloy Version - DE