Lever action with peep sight will be my close range stopper.
When it comes down to it, I'd just rather have the rifle with close range optics, or the iron/peep sights. Just because a running coyote at 30 yards quickly turns into a running coyote at 70, and if he is going away, even at that 50 yards, there is a lot to penetrate. Just leaves that nagging feeling of wounding a dog in my mind, even with 4 other shots to back it up.
So, practicing and being efficient and effective with that rifle at close range, could bring that extra payoff for you should you encounter that coyote that quickly goes from shotgun range (50yds) to rifle range (70yds).
Now if it is open enough to have no worries, you know you'll be able to get your long gun up and get that shot off, so be it, shotgun it is. I'd just rather be on the safe side, using that rifle that will put that coyote down quickly and ethically even if the 20, 30, 50 yard shot turns to 70, 80, 90...