Isn't the AK-47 still the most reliable firearm ever made?
I guess it depends on how you define "reliable". There's a reliable as in "shoots when I pull the trigger no matter where it's been", and a reliable as in "hits what I'm pointing it at".
The AK-47 and the swiss SIG-90 are, I think, two imbodiments of those two kinds of reliability. The AK-47 is nearly indestructible, but have you ever done target practice in the 300 meters range with one? We have. It's not fun.
The SIG-90 on the other hand is so bloody precise that it can serve as a makeshift sniper rifle if equiped with a scope (still pretty straight at 400 meters), but boy will it leave you standing in the rain if you let it standing in the rain without a half-hour mainenance routine afterwards...