I have to disagree with your statement, somewhat. Both rifles are exceptionally reliable, as AR's have come a long way, and are far more versatile than the AK. The AR is much more customizable, and with the implement of the gas piston system, are pretty on par with the AK's in reliability.
All that being said, there is a reason that the AK is the most popular assault rifle in the world. No need to re-hash what has been said a thousand times.
Its personal choice, with the best option being what BigCheeseStick opted for-- own both!