I'm in the market for a barrel vise. Can anyone tell me how well the Ken Farrell vise works? I like the no-insert design, but I wonder how it adapts for different barrel contours. Will I need to make sure I grab the barrel by the shank with this or does it have some method of holding a tapered barrel with contact on more than just the leading (largest diameter) edge? Do the jaws the mar the finish of the barrel pretty significantly?