Excellent bit of info.
My wife and I have been interested in composting toilets for years. We live in VT and they've been around on land since the 1980's in homes and camp grounds. We also have friends who have an Air Head
and love it. However, they live aboard at a marina.
We spent the last 4 years aboard our sailboat and had talked to the owner of Air Head
about one for our application. We seldom used marinas
so didn't use a land head often and tended to the visit more remote
areas. Sadly, we came away thinking it wasn't the right answer for us.
My only suggestion is to talk to the people at Air Head directly and give them a full accounting of your current
and future cruising plans/applications. Then go with their recommendations. Our feeling was that if they didn't think the system was right for you they wouldn't try to sell you one.