My OFF-ROAD POPUP camper has the cassette/shower combo and it works out well for the two of us. The shower works best with you sitting down on the potty lid and using the hand shower. Mine has the shower curtain you can pull around the whole assy...
The potty tank is a 6 gallon two wheeled tote and is easy to pull out from the outside and dump down any bath room you find along the trail. Easy tote to dump... Most OFF-ROAD places we go to has a primitive bath room usually at the entrance. We just dump our cassette tote down their pot.
This is what mine looks like

I really wish I had the potty version only as we usually just wash up at the kitchen sink... The POTTY only version would save us alot of room...

Roy Ken