I have an Explorer II, the pistol version of the AR-7 made by Charter Arms. It's okay, but far from reliable. With the factory 8rd mags, it seems to work okay, but I have several other mags from folks like Ram-line, in both 10rd and 30rd and with them, it jams every other round by crushing the tip of the bullet into the top edge of the chamber. It's more of a novelty than a real "survival" rifle, in my opinion, but I keep mine around 'cause it's fun to play with, and it has interchangable 8" and 10" bbls, so it looks pretty wierd too. Of course, mine is quite older, and they may have improved the design or reliability since then - I think the design has been through at least two other manufacturers since Charter.
-John