Most of the advantages of a cassette toilet when boondocking have already been covered. We find that dumping the cassette at appropriate places is easy whether you have the TC with you or if it is dropped at your camping spot.
We may be at a CG that has no hookups but has a dump station that has a line up.
As it takes seconds to dump, you can empty the cassette yourself In between rigs that have black water tanks as they are rolling up their hose and the next rig setting up.
We find that for the 2 of us, if we conserve water, we can last up to 5 days or more before pulling the cassette and dumping it. It is as heavy when full as a normal suitcase(50 lbs). This helps us conserve our fresh water which allows longer stays out in the bush.
Ours has a light that indicates when the tank is full.
Where our black tank was is now storage.
Dave