My Mini-14 is a 581 series, but one of a special run built for Davidson's. I bought it new a couple of months ago. It has a very nice Circassian-walnut stock, blue steel, and the normal (for a -14) flawless functioning. About 400 rounds, all handloaded, have now gone down its tube with zero malfunctions.
My handloading experiments are continuing, but already it's giving me sub-two-inch groups for TEN rounds at 100 yards, fired at around thirty-second intervals. In my rifle at least, barrel heat doesn't seem to be much of an issue. It has a Leupold Compact 3-9x scope mounted in the Ruger rings.
It's purely my opinion, but I simply dislike the AR-15 rifles. Being an ol' fart, I think I'm allowed to say that I abhor aluminum/fiberglass, AND the physical layout of the rifle, AND the appearance, AND its handling qualities. On the other hand, I really like my FAL...(of course, it has all-walnut furniture) so I'm not completely out of step. I certainly recognize the strengths of the AR types, but I just don't want one.
I'll take the Ruger -14, hands down.