I've posted on this forum and others several times looking for information on replacing the Vacuflush system in our 2016 Southwind.  I knew when we bought  it several years ago the complicated, loud, expensive toilet system would be a problrm, and I was right.   The first time it failed i replaced the pump system ($800) myself, which took several days and required cutting two access hatches under the bed to be able to get to it.  When it failed again (bad electrical connection) I got it going but decided enough was enough.

I won't go into all the details but I bought a Dometic macerating toilet and installed it myself.  I pulled out the Vacuflush pump system and connected the toilet discharge hose directly to the black tank inlet by splicing in a short piece of hose.  I had to run power into the head as the new system requires considerably more amperage than the old one.  With a slight modification of the old flange the new system fit right in place.

So far I could not be more satisfied with the conversion.  I'm offering this information to hopefully help others with this issue.  I know there are a lot of Vacuflush systems out there, and they work well---until they don't!  If it was easier to access the pump assembly i might have kept it, but I'm too old to crawl around in tight places any more!  Anybody want to buy some Vacuflush spare parts?!?!