We've had cassette loo in the past, but have had a separator composting toilet for ten years now and we wouldn't go back to cassettes. Believe me, emptying the solids into a bag is a lot less unpleasant than emptying a cassette. We put coir fibre (from pet shops) in the container each time we start and empty ones and that works well. We bag ours up and take it home at the end of a trip. It goes in the garden compost and rots down nicely. I would never put it in an elsan point, its much to dry and solid and would probably block it. The pee of course can go in the elsan point. A properly installed composting loo with an air flow pipe and fan to the outside should have no smell whatever. The pee goes in a separate container and we have found it useful to buy a second pee container so we can go for longer between emptying points.