Over the years I have like alot of people used different things. but to me I think a file is the way to go on broadheads with the correct hardness. To me it just seems that once I use the file and have a hair popping edge, still slightly serrated, naturally. the keen edge of razor sharp broadheads, like any honed edge will in shorter time in field become duller. I feel alot of guys forget that moisture and/or just rubbing dull's the edge of a broadhead. That is why in the older movies Fred, Howard and others, would inspect and touch up the heads with a file, easy to carry, quick touch up, and kept that jagged edge for a great cutting through tough tissue. Just my opinion. Note: as already said, let the tool do the work, light for sharp.