The AR is not more difficult to use than the AK, but it does have more buttons that can confuse an inexperienced user. The AK has a lever that is the safety and is located at the bolt. Push the lever, cock the bolt, then fire. Lever up for safety and magazine release at the magazine. That’s it.
The AR on the other hand has the bolt on top of the gun, the safety on the left hand thumb, and the mag release in front of that. I take both my AK and AR shooting when I go with my friends. I have never had to show how to operate the AK more than one time, but the AR always invokes more questions and blank stares when people are trying to figure out which switch does what. No doubt it is an easy gun to operate, but its design is not quite as simple as the AK.
In addition, I occasionally have problems with my AR jamming, but I don’t have problems with my much cheaper and much lower quality AK (probably because everything is so dang loose on that gun). There is no doubt though that the AR is a much tighter and better quality gun and the availability of ammo is better than 7.62x39. I’ve been waiting for 3 months now for my bulk order for my AK.
The AK safety, if used, cannot be released with the right hand unless it is removed from the pistol grip. Reloading is slightly more difficult and slower, but an accomplished operator can get the job done quickly.
The AK's greatest drawback is that the bolt/bolt carrier does not lock back on an empty mag. The loudest sound in the a gunfight is "click" on an empty chamber.