I should clarify what I meant by "a breeze" -- meaning that the waste is fully composted, so that there is no excessive odor when handling the maintenance procedures.
The people maintaining modern solar toilets could give you the best answer to your question. I happened upon the Nevada Falls toilet being maintained once. He showed me the system and what he had to do. The worker (a contract employee) seemed fine with it and I didn't notice any objectionable smell. Rangers have more important things to do. I think a lot of the objection to toilets came from their bad experience with an obsolete design that wasn't working.
