I am a sucker for realism. 90% of my airsoft gear and outfit is government issue or meant for tactical operations (not airsoft games). Classic Army externals are by far the best out of every other brand. The gun is heavy and extremely solid. What isn't metal is nylon fiber and also very durable. Classic Army again trumps all for having the best external parts you will ever see on a replica gun.
Now for the bad news.... CA internals are notoriously finicky. Some others have complained about taplet plates and such. However, the gear box and gears are solid. I personally recommend buying a Classic Army for the externals that you want and then upgrade parts (you'll do it on any other gun anyway). Luckily for me I haven't had any of these problems anyway (and the gun is 2 years old).
My last recommendation is to get a silencer attachment and a standard M4 inner barrel. That way you still have a smaller gun than the standard M15A4 but your barrel length will be the same and you'll have rails and an excellent stock.
- Realistic Externals
+ Steel parts
+ Nylon fiber stock and grip
+ Laser engraved insignia
- Flip up and removable sights
+ Adjustable like the real M4 sights
+ Sturdy (feel free to bang em against the Humvee)
- Excellent ROF
- Mediocre internals
+ Upgrades are necessary, but you would buy them for your KWA anyway
- The included magazine wobbles
+ Easily fixed with tape; other brands work perfectly.
Rating: [5 of 5 Stars!]