I'm basically crafting my own G4 right now because they're all out of stock. I bought a G&G GR15 raider with the metal rails, a madbull outer barrel because the front sight is welded on and I want a cleaner look, and some MBUS sights and an MOE motor grip. I also got a silencer and am getting a longer inner barrel so I can convert from CQB to field. I get to customize whatever I want. The base gun is only 200 and then go from there. Changing the externals of a gun isn't hard if you have an allen wrench.