Always a good idea if paying someone else to do your chains is too have a look at some chains they've sharpened. My Stihl dealer really went to town on some chains I left with him too sharpen. Removed a good 1/3+ off each tooth, cooked most of them & did'nt touch the rakers which is a must if your removing that much off the teeth. But I was busy, had a grinder on order in the mail & was left with hand files & cooked hardened cutters which is not the best combo. That was near a decade ago, I learned my lesson. On the subject of grinding wheels, a few months ago I stocked up with 6 new spares (2 in each size) & I'm with Philbert on the pink wheels, I like them & prefer them to CBN's. I can 'tune' the profile on them to get the side plate shape I want in our hardwood. Honestly the $5 pink wheels I buy I wouldn't swap for $100 high end wheels with big marketing claims attached too them. Its human nature too expect the more we pay for something, the better it must be. Often this is the case but not always.