Four knives is not much wear, and a slightly dished 1000 is mostly a problem for wide flat blades like plane irons. For kitchen knives a small hollow is survivable. Do not let flattening anxiety stop you from actually sharpening things.
Ray Pellerin
@bench_dogged
Twenty-two years as a finish carpenter, now mostly cabinets and built-ins on weekends. I know more about scribing to crooked walls than any person should.
Folded rather than chipped, in oak, at 30 degrees, points at the edge being too thin for the work rather than the sharpening being bad. Chopping a mortise is impact work — the edge is driven into hard end grain repeatedly and 30 degrees does not have enough steel behind it.
Take the micro bevel to 35 degrees on your mortising chisel and leave your paring chisels at 30. Two seconds more on the stone and the edge lasts several times longer. You lose a little of that first-cut glide, which does not matter at all when you are removing waste.
One more variable: is the maple board actually flat, and is it what you always use? A hard, slightly cupped board means you land on the tip and heel first and put all the wear in two spots. My edges lasted noticeably longer after I flattened mine.
For what it is worth, feeling for a burr with a thumb pad is unreliable past about 3000 grit even for people who have done it for years. I use a magnifier at that point and I would rather admit that than pretend I can feel a micron of steel.
Whatever you buy, keep the reprofiling angle honest. Marker on the bevel, six strokes, look at where the ink went. Old pull-through damage leaves a convex bevel that lies to you about the angle you think you are holding.