Very true about sharpening with a belt grinder. Someone competent can do a fantastic job on a knife. If they are not competent they will ruin the knife for sure. I won't let anyone use a belt grinder on any knife I own, too much at risk.

I sharpen my own with various stones. I have Japanese waterstones in 3 grits, a Spyderco Sharpmaker with ceramic stones for double bevel knives and I strop with a leather strop with green buffing compound.

I also have an Edge Pro Apex setup for the harder to maintain angle blades. No power tools in my sharpening. I know belt grinders work wonders but it can be a good wonder or a bad wonder. A long time ago I worked at a place where we used large shears and someone came around about every month to sharpen them for us. The guy was awesome on the shears, they really cut well when he worked them. I once had him sharpen a Solingen hunting knife that I had bought when stationed in Germany. It was ruinded. The guy knew shears but was clueless when it came to knives. So, no belts for me.