The 70M has a dry bath, as far as I know. Very few B van conversions do, but it does, at the rear. Look at the floor plan.
Personally, I believe slides are prone to failure, and the bigger the slide in a B van, the more chance of a problem. Just my opinion.
The ERA 70M is probably the heaviest build of the floor plans, due to the Murphy bed and slide, and as such, the OCCC will be the smallest.
There are some good video reviews of them out there, watch a couple before you decide.
Also search for "2018 ERA 70M problems", and see what you find.
2018 (2017 Sprinter Cab Chassis) Navion24V + 2016 JKU (sold @ ????)
2016 Sunstar 26HE, V10, 3V, 6 Speed (sold @ 4600 miles)
2002 Roadtrek C190P (sold @ 315,000kms)