AS far as the "fun" factor is concerned, ther may be no "funner" gun to blast away with than an AR-15 clone. I recently took Doomsday and his father-in-law out to shoot with about 300rds of surplus ammo. They never could get the $hit eatin' grin off of their face the rest of the afternoon.
It is accurate, fun and cheap to feed with ammo running around $.10/shot (bought by the case) That is almost as cheap as a paintball gun! Hey there's an idea for you...how about a good paintball gun!