I have a WE G36 (used to be a C)... It is a very nice gun to work with. It's rate of fire is excellent on propane/green gas, and I've never had any problems with it really... The only two things that I've had problems with are in the magazines. They have a join in the center... Probably something to do with that triple chambered evap system that they say makes the gun perform more consistently. There is a seal there that sometimes comes unseated when the magazines are empty, but it has always sealed back up when I charged it with gas. The second issue I ran into (once) was trying to fill the mag. The plastic outer casing is only held onto the metal innards by a plastic tab and a single screw on the bottom. That plastic tab is maybe 1/8th of an inch thick, and while charging one of my mags, it broke, and one of the parts that operates the bolt lock fell into oblivion. Just support the innards by holding onto the top of the mag while you are charging it and you should be good.
EDIT: also, it is compatible with some AEG parts like handguards and upper rails and such... I have a CA SL8 hand grip and rail on mine.
For $220-$260, I think it is totally worth it. Skirmish-able out of the box (IMO), nice and comfy to use, and easy to work on.