The Steyr AUG magazines are the finest in the world IMHO. Unlike the AR magazines which only has one point of attachment to the lower receiver, the AUG magazines have 2 points of attachment. Just this alone makes them a 1000% more reliable. Also, the AR magazines were initially designed to be "disposable" and thus made of aluminum. Or, more probably, they were made of aluminum to prevent electrolysis with the aluminum lower receiver. If they were made of steel, the aluminum receiver would pit due to it giving up electrons to the steel. And, thus, it was rationalized to be "disposable". As we all know, no one treats them as disposable. Being of a relatively soft metal, the aluminum magazines warp and deform with use and abuse which results in FTF and a host of other problems. The weakest link of any magazine fed firearm is the magazine itself. BTW, Mako makes excellent Steel magazines; but, they have been coated with a very tough finish (I appears to me to be a type of baked on enamel)which prevents electrolysis. They are better magazines than the US GI ones but they still attach to the lower receiver in the same way.
The AUG mags also have been tested extensively against chemicals, drops tests, being run over by deuce and half, against extreme exposure and temperatures, etc.. They are much more durable and reliable than any other magazine system on the market. I would bet my lunch money that an AUG will be more reliable than any AR you care to pit against it. And if you are trying to decide between the AUG NATO vs the original Steyr stock, it is a no brainer! Get the original AUG stock. Stock up on all of the AUG mags you can get a hold of; they will serve you well and are better than gold should you need to depend on them with your life or that of your family. I have AUG magazines that are over 20 yrs old and they still function flawlessly. I also have aluminum AR magazines which are less than 1/2 that old which are now toast. I have tried rebuilding them with new followers and springs and they still are not 100% reliable this is most likely due to the [soft aluminum] feed lips "relaxing" or getting warped over time.