The Bulgarian SA-M5 milled 5.56 AK I had would group as good as the service grade Ar-15s I had.
I traded it for the stamped version and lost a little accuracy. I should have put a sight block on the SA-M5, because my eyes were getting too old for iron sights.
I still regret not getting an AK when they were still relatively inexpensive. I do enjoy a good SKS, though.