I haven't used them yet but those VPA's look awefully good.They should be a no brainer to sharpen if you have a good flat stone.Even if you don't have a stone,you can get some different grit wet or dry sand paper and lay that on a plate glass,steel plate or some other hard,flat surface.Start with 220 grit and work finer as you see fit.
At any rate,you need to learn to sharpen.You should practice with broadheads to assure proper flight,so you have to resharpen after.Broadheads of course need resharpened after shooting at game and they really should be touched up after a few days carrying in the quiver.
I think texbow2's suggestion is a good one.