Well, I have limited experience with the G&G (broke it in for my buddy) and it is a good gun, but not great, and it's supposed to be one of the best SCARs made, certainly better than the CA, and equal to the VFC.
If it were me, (not to sound like I'm beating a dead horse) I would get the DBoys, and use the money I saved over buying either the VFC or the G&G to get a better motor, a top notch hop-up and tightbore barrel, reshim and regrease it myself, maybe add some different internal parts, and then have a gun that is internally better than the "high end" gun for the same or even less.
The body on the DBoys is great, and the trademarks are the best out of ANY SCAR on the market, high end or not (if you order it from HK). It just lacks a bit internally, but that can be EASILY remedied.
I look at it this way:
I can buy a $400 "high end" gun and call it a day. The parts will be good, but not great, the worksmanship will be good, but not great, and the gun will probably last a good long time without ever needing to be opened.
Or I can buy a $180 gun and throw $200 worth of absolutely top notch parts in it, do the work myself so I know that it got the time and attention it needed to be done right, and have a gun that uses GREAT parts and GREAT worksmanship and will last a tremendously long time, because it got the attention it needed. I will have a gun that isn't a "cookie cutter" gun like everyone elses on the field. I will have a truly unique gun that outperforms pretty much every "high end" gun on the market, for less than they paid. Now, usually you make some sacrifices when you do this, like having iffy externals, but in the case of the DBoys SCAR, the internals are on par or surpass (in some cases) the "high end" guns.
This is one of those cases where the middle end gun is the better option over the high end.
Why people have to have the "high end" gun is beyond me. With a little love, even the lowliest ACM gun can perform with (and above) the big boys, there's absolutely no need to blow all your cash on it because people refer to it as a "high end" gun. With most "high end" guns you get a high end name and a high end price, nothing more. Sure, some parts may be made of a more expensive material, but does that make it automatically better? No. The QC may be better, but if you do a quick once over on the internals, didn't you basically bring it up to the same level? The performance will be about the same, (or better if you tune up the mid-end gun) whether it's "high end" or not, so it's not like you'll have an advantage over anyone.
But, it's your choice, and if you feel more comfortable compromising some things and getting the "high end" gun, then that is what you will do. No words of wisdom will change your mind, lol... This was a long rant and wasn't all directed at you, mostly at the people who hold "high end" guns above ACM guns for no reason other than because it comes from a better brand name, with no other basis.
Good luck, and have fun!
(Oh, and most likely no one on this site will have experience with the "high end" SCARs, so I suggest asking on another forum if you want real honest answers)