After a long search, we had settled on a new Zion. We liked the under-hood generator, solar panel and floor plan with the open back along with screens on both the side door and back. When talking to the sales person about whether it made sense to buy to spec or the one they had in stock, we mentioned that there was a used 2015 Roadtrek RS we were going to take a last look at before finalizing the decision. It was about the same price as the new Zion. He said if we could get the used one for the same price, we should take it. Unfortunately, it lacked the under-hood generator.
Then a used 2015 Roadtrek Etrek turned up for the same price. It has the under hood generator, solar panels, is all electric with 8 AGM batteries, diesel heat and had the Mercedes Sprinter diesel chassis. So we bought it. Its downside is that it is much larger than the Zion and lacks the screen on the side door.
We are happy with our purchase, but would also have been happy with the Zion. If the Etrek turns out to be more than we need, we would certainly consider getting one in the future.