The AUG is the Real deal, just in semi automatic form for us. AUG stands for somthing like "Armee Universal Gewehr". It has a Flash hider, a pistol grip, and a forward pistol grip. (That forward pg, may be aftermarket) These were banned from import by Daddy Bush's non sporting intent import ban in '89. Imported rifles after that point could only have one of the "evil" features we all talk about. The one that is always chosen first is the detachable magazine.
The USR (Universal Sporting Rifle) is an AUG with an unthreaded barrel, and a stock that had it's pistol grip altered enough for the Feds to consider it a thumbhole. Ergo, the only evil feature it has is the magazine.
Keep in mind that the rules have changed since then, so even the USR wouldn't pass now days.
The bottom line is that the USR is a postban AUG.
The AUG:
[IMG]http://albums.photopoint.com/j/View?u=36353&a=1534340&p=16174895&Sequence=0&res=high[/IMG]