There is a photo of a Sewer Solution attached to a Roadtrek at this link: https://sites.google.com/site/roadtr...sewer-solution
You can see it is mere inches off the ground.
It depends on what problems you are trying to solve.
If getting down near the ground to attach fittings etc. is the primary problem then I don't think any portable options will help much. A permanent macerator installation would help.
If pumping waste uphill or over a curb is the primary problem then a portable macerator, a sewer solution or a permanent macerator will all solve that problem.
All of the portable options need to be stored somewhere so sometimes that creates a new problem - finding space for it in a Class B.