Depends, Is the G&G Ak47 one of the clearsoft ones with the wood? You'll have a 'lot' of trouble replacing the body with a metal one since G&G's are uniquely styled. I own a G&G plastic version (TM styled, yay) and it fires like a goddamned beast before upgrades... I just got a freind to slap a modify piston/cylinder set and its just amazing.
But, if anything, go for the AUG, Scoping AK's are a pain without making them look ugly as hell. That, and augs are particularly unique compared to the hordes of armalites used.