I’ve been reading nearly every Newmar post for over a year and a half ( and a lot others) and for that year DS, basically before 2018 or so, I haven’t seen anything significant. My 16 Ventana only had three very minor after-sale issues, two of which were recalls by other companies.
I do have failing clear coat on the radius edge of the roof in a few spots, but the DS roof line is a different design. Still you might take a look at that. I ave Hehr windows and have heard no reports of issues with them - it’s all been Lippert which happened later.
I’ve also heard of some upholstery peeling but if it looks ok, you material isn’t failing. Mine is perfect and the coach hasn’t been stored inside. Otherwise it’s pretty much mileage and maintenance records to ensure the rig has been treated well.
2016 Ventana 3427