Don't mix up a cassette toilet with a porta potty....
The cassette waste
Outside pull out section container pulls out from the outside of the camper, it never sees the inside, inside you have a regular TC toilet without a black tank underneath, it has a water supply to flush etc...
Inside of camper:
Inside of camperYou pull out the unit, walk to the spot you choose to dump, unscrew the cap (not shown in the picture) press the air valve, invert the container and swoosh out it goes, takes about 15 seconds...
We dump at anyplace that receives sewage, pit toilets, flush toilets, dump sites etc.. dump every 2 days, there is always a place to dump.
Also you don't need potable water to fill the water tank section, any old brook or stream will do. Also dont need a hose.
If you want complete dumping freedom it is the way to go, if you are in a camp site all the time I would prefer a large black tank on the camper.
The most difficult place to dump a cassette is in the regular North American campground type dump station with the hole and cover plate.
If stuck with that type of dump I will choose an unused site trailer type dump pipe and just pour it down that pipe.