I have a Promaster based SMB with pop-top and toilet/wet bath. I had to have them use the top for a Ford rather than the standard Promaster top to keep the height down, but it fits in the garage with an inch to spare. The Danhard was installed under the rig, and works well enough that I've survived in Phoenix in July.
If you go with the wet bath, get one of the synthetic chamois cloths to help mop all the water to the drain you can, then mop up what won't go down the drain and wring it out into the toilet. It will REALLY help the bathroom dry out after a shower, as will running the Danhard + heat.
My rig can sleep 2-3 people with the top up, and one with the top down. Since I'm normally by my self that is good enough.