First off, all of the externals on this gun are literally the exact same as the G&G combat machine AEG, they are all plastic, yet very strong and durable.
As for the internals of the gun, the disassembly is super easy, literally 2 pins and you can remove the whole gas system. Once the gas system is popped open by unscrewing 5 phillips head screws you can tinker around with the internals, it is a very simple gas system and easy to fix.
I have had this gun for over a month now and it worked amazingly well until the last week or so. An o-ring in the piston or whatever you want to call it where the gas goes through, broke and gas leaked after 1 shot. Using the few o-rings I had laying around none of them worked, but it is (in theory) a simple fix.
Overall the gun is maybe 5 or 6 pounds and about a third of that weight is the full metal mag.
Speaking of the mag, the mag that came with my gun sucked, I only got 1 or on a good day maybe 2 full mags of bbs off on 1 gas fill. My friend got the exact same gun and his mag gets around 4-5 clips off at 70 degree temps ( I think I just got a lemon). The mags hold 30-40 rounds each. Both me and my friend's mag jams occasionally, but spray a little silicon oil on it and you're good.
Extra mags GHK brand mags and other websites (Evike) have them.
Another cool thing with this gun is that if you wanted to, you could put a version 2 gearbox and a motor in there, wire it to the back, and bam, you have an AEG.
Being a gas gun, the fps varies depending on the temp, when it was cold outside (around 50 degrees) the fps dropped to around 380 or 400 and I did not get may shots on each fill of gas, but in the Texas summer it could possibly reach 500 fps with the tightbore m16 length barrel I've installed.
I recommend using propane, yes it smells but saving money _ 5 secs of bad smell each mag fill.
If I have left anything out, please refer to the facebook comments and replied that are posted below, I'll try to keep those updated.
Compared to other gas guns, for the price you cannot beat this gun, but if you have the $$ I would rather buy a PTW or some sort of GBB DMR.
High fps (Pro or con)
Durable plastic externals
Lightweight (Pro or con)
Super duper simple to disassemble
Most repairs,if any needed. should be simple (o -rings for mine)
Lots of rail space
Realistic in terms of mag capacity (pro or con)
Pretty good kick for an airsoft gun, feels like a .22 cal.
Iron sights are reliable and full metal.
CAN BE TURNED INTO AN AEG IF YOU HAVE THE GEARBOX AND MOTOR! (would be useful in the winter)
Mag (Mine might have just been a lemon)
Temp effects performance, not a winter gun unless you're in Texas, where there is no winter.
Cannot remove the front triangle sight (gets in the way of some optics)
Orange tip was hard to get off, I eventually used a soldering iron to melt it off.
Mag occasionally jams
Have not found spare mags on GI yet, but have on other sites.
For a gas gun at this price, you can't beat it, but if you have the money I would get one of the PTWs or something.
I'm giving this gun a 4/5 because I have already had to do some simple repairs in less than 2 months, and the mag it came with kinda sucked compared to my friend's identical one.