Lichtsinn recommended we do the front alignment after 1000 miles - which we did at our local Sprinter service.
But, we still had a pretty rough ride at highway speeds.
We took our 21VD to a tire place and they were unable to get the front tires to balance. We took the RV back to Sprinter service - and they were also unable to get the tires to balance.
They asked about the "goo" in our tires. Lichtsinn sold us tire sealant as part of our purchase. Sprinter service removed the sealant (cost = $500) and was then able to balance all of the tires.
And when we took a 3500 mile road trip over the last week - we have a smooth ride for the first time since we picked up the RV (we initially thought all Views had a rough ride...).
It's possible we had a tire out of balance when the sealant was added. It's also possible we have a defective tire - though 3500 miles of smooth driving seems to rule that out. Or... the sealant was bad, clumping up and causing the tires to have a rough ride.
So if you're having a rough ride - the front alignment is a first step - and if it's still there, get all of the tires balanced (road force balancing)...
And probably avoid putting any sealant inside the tires...