In the market for a dedicated bolt action slug gun for whitetails. I have narrowed it down to the Savage line of sluggers. Now which chambering, 20 ga or 12 ga? My dad has a Marlin 512 and it is in my opinion way more gun than anyone would ever need for a Michigan whitetail. I am leaning towards the 220, that way my wife could use it as well without fear of it nocking her senseless. Tell me your personal experience with either gun and/or why you would choose one over the other. Any known issues I need to be aware of on either weapon?

Thanks,
Z