" an even moderately maintained AK. Ammo is reasonable too, and in short range defensive situations"
Glad you mentioned that for all the folks that have, or, will purchase one... A lot of the bad guys have purchased these as well (Hey! Spare parts and ammo once you've eliminate the threat!).
This is exactly why one should have a Scoped long gun... a .308, 300 win mag, 30-06, 7mm etc is handy to take them out before they get in range for their weapons!
Also, don't forget the benefits of a good suppressed firearm, specially at close range.