We all have our own experiences and I am just speaking from mine without any special data to back it up so take it for what it is worth,
There is a lot of variation in sharpening and a lot of the current buzz centers on prepping of smooth plane blades and flattening chisel and plane blade backs. My experience is that there is way too much emphasis placed on flattening stones for much of sharpening. Tools such as most carving tools, drawknives, cambered plane blade bevels, etc. really don’t require really flat stones.
I think I have used everything (scary sharp, oil stones, ceramic and diamond)with the exception of Waterstones and I haven’t gone down that road (yet?) simply because of the increased maintenance of the stones. I would rather just shape and sharpen my tools and get on with my work than spend time flattening stones. I used to flatten (and de-glaze) my oilstones (on sandpaper or coarse diamond stones) for the ones used for smooth plane blades, and chisel and plane blade backs. I now usually use diamond plate stones and have been pleased with them because I feel they can maintain their flatness to a reasonable degree, for me anyway. The cost isn’t really all that bad over the life of the stone. I have had mine for several years now and they don’t just suddenly wear out, they just create a finer finish and slow the cutting as the diamonds wear. Edge touchups require little time and working blade backs are normally done just once during the life of the tool. Frequently I will also use sandpaper for shaping (flattening) and then turn to the diamond stones to bring the surface finish to the point of honing, with the final finish being a simple compound charged MDF strop. Not as sophisticated as a series fine waterstones but quick, simple, and relatively inexpensive. The resulting edges most certainly give me good service.
Anyone preferring a different system most certainly won’t gat an argument from me because they all work. This just happens to be my preference in my shop.