I would love to try out a Marlin 1894 in .44 Mag for deer hunting...of course, I would also enjoy trying out my brother's father-in-laws Winchester lever action .45 LC.
I would equip the Marlin with a compact scope (since the entire rifle is only 36" long or so...look wierd with the scope sticking out past the barrel...LOL) and quick release rings, so that the open sights could be quickly available...
Most ML sabots are .44 caliber slugs, so I would imagine that you would get similar performance (my experience has been very positive).