Hi guys. I'm not particularly new to Airsoft, but I am fairly new to owning my own AEG and completely new to upgrading internals. I've got myself a G&G Combat Machine (CM16) Raider. After doing some reading on the net it seemed to be the best option based on performance vs cost and seemed like a reliable beginner/intermediate purchase.   So far I am quite impressed with it, but I am now looking to get myself a second, better quality M4 and upgrade my CM16 once that new, sexy beast arriv