We’ve been using an Air Head composting toilet since 2002 and it has worked beautifully. No holding tank to deal with, no smelly hoses, no problem proving we conformed to the “absolutely no discharge” rules in areas like the Great Lakes and Lake Champlain. No pumps, no clogs, no moving parts. We are on a sailboat and a big plus was the storage space we gained when we got rid of the holding tank. We also freed up 2 thru-hulls when we removed the old head, one of which will be used for a watermaker intake and the other for a manual seawater pump at the sink in case of a power failure. The toilet itself is virtually odor-free (there is a slight scent to the peat moss “desiccant” when you first set it up) and the active vent improves the overall air quality and ventilation in the boat.