I have 2 VacuFlush heads in my
boat. Although you
can flush with little water, it is still a good idea to flush at least a quart of water through the system once a day to keep everything working well. The
toilet can sit in a small space with very little room behind it as the
pump and the rest of the workings will have to take up room elsewhere.
Despite the fact that my heads are only fresh water flush, I recently had to clear out a big calcium blockage, which I thought can only happen if using
salt water flush. So, more water through the system should eliminate that problem. Granted, it has only happened one time and the system is from around 2001, so 18 years to build up calcium is not bad.
I took a brief look at the Raritan system and it looks quite nice. My concern would be how much space is needed behind toilet for the
pump machinery.
If I were to install new, I would take a careful look at the Raritan system, looks good. I have read that Dometic has a new, very quiet pump.