Rob,
I have never tried bore butter, but I have used unscented Vasoline for years with excellent results. After you get the broadhead shaving sharp, put just a dab of Vasoline on your index finger. Rub index finger and thumb together, then carefully, from the ferrel to the sharpened edge, rub on a very light coat. It doesn't take much, just enough to make the blade look oiled.
Deer won't smell it. If done with a light coat it doesn't add weight or collect dust. And the biggest plus, your broadheads will be ready to use when they are pulled out of the quiver all season long.