I had similar concerns regarding separation of liquid and solid waste with our Nature's Head. It turned out not to be a problem. One of the greatest advantages is the amount of water conserved by not having to flush. There is also no odor. It's easy to keep clean with a spray bottle of white vinegar. When disposing of the solid waste there is a not unpleasant "earthy" odor. Urine capacity is about 3-4 days. I have a nylon tote bag that is used to transport the urine container to a toilet in order to be somewhat discreet about the process. For my grey tank I have garden hose adapters for both ends, but have never used a dump station because we usually just empty it in the yard at the end of the trip. When we set off on longer trips I'll probably have to deal with dump stations for the grey water. For me, the composting head was worth the extra expense.