not bad, looks like you ended up at just about $10 a lap. not worn ou6t till its shiny.i have a couple laps that slowed down and i bought some sets of sharpening rods/sticks on ebay, a set of 6 diff grits, and took the appropriate grit to the disc with plendy of water and bingo dressed it to a new cutting surface.—- removed a little plating.