Yeah, I'm an admitted Knights Armament fan. But not blindly so. There are several things that they do that I don't like. But if they sold E3 barrels and bolts, I wouldn't use anything else.
And you're right about the Tula ammo. But it was an ammunition test after all. The gun running brass cased 223, ran like a top. The tula ammo was definitely a problem. If I recall, it plugged a gas tube.
Filthy 14 did have some minor maintenance performed. But there are a few things to consider. 1) those guns are used to train mostly LE, so some preventative maintenance is normal. Just like most departments and the military regularly swap buffer springs, bolts, barrels, extractors, etc all according to a predetermined pm schedule. 2) the gun performed extremely well under an abusive firing schedule and was pretty much neglected in terms cleaning regimen. They were trying to make it fail. Bottom line, we all clean our guns before they get that nasty and a reasonable amount of maintenance is all it really takes to keep one up and running.
Just to be clear for everyone, I'm not trying to make an argument that an AR is superior to an AK. Just trying to illustrate that some commonly held beliefs may be misplaced. Either one would serve you well if you really needed it.
For me, the ability to easily add an optic, light, etc is a big factor. Also, the lighter weight and better accuracy at distance, along with the ability to run the gun faster at close range, steer me to the AR. It's just personal preference.