Congrats on your new trailer. I have been doing quite a bit of research on composting toilets and will definitively install one in my Tradewind. I'm changing my entire floor plan and will build a wet bath to save space.
As an other alternative (besides Air Head) also check out C-Head. It's a simpler design and a smaller unit, as well as about $300 - $400 cheaper. It uses cheap 5 gal buckets with a lid from Home Depot for solids and 1 gal milk containers for liquids. Website: C-Head portable composting toilets
I contacted Nature's Head to inquire about using the toilet it in a wet bath and was told there is no problem as the top is sealed. The only thing to do is to drill a few drain holes into the liquid container holder (not the bottle
). C-Head on the other hand would need some kind of cover or be behind a shower curtain, which is not a deal breaker to me.
Keep us posted on your decision and how it worked out!