I'm voting M14/M1A.
Aside from reliability and accuracy, one must not discount ergonomics
Yeah, I read "Boston's Gun Bible"...the gun parts, anyway. And I agree with much of his rationale.
The AK-47/AKM rifles are not "battle rifles", but "assault rifles". Most sources of information make this distinction. I just sold my Yugo-built AK off to fund the purchase of a CMP "Special Grade" M1 Garand and I absolutely do not regret that decision.
If your goal is to arm a bunch of illiterate cannon fodder so they can rush in close to the enemy and spray at close range, the AK is the rifle for that. You have to get in close with those arms. At Fort Riley's private weapons range I was NEVER able to hit a man-sized target at 300 yards with an AK. I tried two of them, one a Norinco and the other a Hungarian SA-85M. Mind you, I was trying to hit a 300 yard target from a bench off of sandbags with me sitting in a chair and I couldn't put a round on paper.
The SA-85M was about as good as you could get, quality-wise, for the AK design.
That alone should be enough to disqualify the AK-style, but you can still kick the thing when it is down. The "third hand" style magazine catch/release is decidedly inferior to the M16. The manual safety on the AK is just about the worst I've seen on any modern semi-auto. Try being stealthy in the bush when you click off that safety and everyone in the county hears you doing it.
The sights are no great shakes either. Not easily adjustable for windage without that c-clamp tool and the sight radius is very short and the front sight post very thick. It is decidedly inferior to any rear peep/aperature sight America has been using since the Springfield 03A3.
I have to agree with Boston's rationale for rating the M14 just a hair above the FAL in terms of the best battle rifle. Some FAL rifles have that funky folding charging handle on the left side of the receiver. I wouldn't want to mess with that if I needed to clear a jam and I was wearing gloves.
Accuracy-wise and reliability-wise, the M14 and FAL...both contemporaries, are arguably equal. The M14 edges just ahead for reasons of ergonomics.