I own several composting toilets. I am looking forward to something far better.
If you want to "flush" to the composting location then you need an ultra-low water head. This is problematic for many reasons. If you don't want a flush then you need to rely on gravity and need a vent fan to keep the bad air out of the house. This is problematic too.
If the compost gets too dry, the process slows, and you end up with fungus that attracts fungus flies. If the compost gets too wet, well ewww.... you have to clean out the system before it overflows.
In winter the compost may not generate enough heat to keep the system from freezing. More ewww...
It is especially difficult to run a system with guests. Imagine spending 10 minutes explaining how to use the toilet. What can go in, what can't, how to flush, what is that stuff down there...