We have bought 2 TTs from 2 very different dealers. The first was a low end starter TT from a large dealer. Their service was excellent. Any problem was repaired quickly and without fuss or return visits. We wanted a specific TT for our upgrade that that dealer didn't sell so we bought from another dealer. Their service was horrendous. 2 times they backed my TT into something and didn't tell me. When I discovered the sloppy repair later they denied it. Almost every repair took a minimum of 3 visits to get it fixed right. I gave up on getting the brakes repaired properly under warranty and finally took it elsewhere and paid for a warranty issue. The last time they worked on the brakes they didn't adjust them at all and at the first traffic light, I sailed right through it. I found that the manufacturer was very willing to work through warranty issues but the dealership couldn't pull the trigger and fix it. I was very glad when the warranty expired as I could then fix it myself and have confidence in the repair.
The upshot is that not all dealers are equal and I will research their repair departments before we buy our next RV if I buy from a dealer.