Boat Heads are highly recommended to have aboard almost any vessel. Small boats can utilize a porta potty while larger boats and yachts can have elaborate marine heads with disposal tanks. In either case a marine head can be a blessing and can also be a real pain in the @%$#@. For example it the end user (literally) is not familiar with the operation of the marine toilet then the unit can and will become clogged up. On my charter boat this occurs even though we inform everyone that they can only use tiny pieces of toilet paper. With out fail a few times a year the head becomes backed up and clogged. Most times this just means a messy clean up and unclog once back at the dock. Once in bad weather the head was completely clogged and filled to the top of the bowl. It was horrible. The S@%$% was splashed around and 4 feet up on all four walls of the head. Enough with the horror stories. IF you purchase a good quality marine toilet and educate everyone aboard the boat you should have years of unobstructed use.