I can take it or leave it. I rarely turn it on, and only if its draining slowly. I do not use it purposely for food waste, and honestly don’t know why anyone would.
I’ve had to clean out some nasty clogged pipes before that handled sink waste. Maybe if everyone saw what kind of lovely buildup accumulates nobody would use these things.
@MajorHavoc has it covered. It’s the flush valve that varies most. Most common is the flapper design, but some brands use plastic towers.
Fill valves are almost universally interchangable. Your variables there will be age and interference. You’d have to go back to basically antiques before things become incompatible. As for interference, units with the big float on the end of a rod may not fit in a tank that uses a tall flush valve. They make more compact styles for those situations.
All that bring said… What are you trying to fix? The flush and fill valves are by far the most common maintenance items, but if neither of those things are the issue then you’re going to run into proprietary parts fast.