Ernie,
That's an old Bismarck, a coveted razors of yesteryear. I would think your grandfather would love to have you use it. That as well as your grandfather's other razors. A quality straight razor, especially passed on from your grandfather, is meant to be used.
Have the razors honed properly and use them. I'm sure you'll feel his blessing.
At least that's what I would do in your situation.