I've talked with several dealers. The last place I bought my 5er from was about as honest as they come. Thunder RV in La Grande Or. The place I bought my previous TT from was mostly liars but fairly honest. They lied about certain parts of the sale but they were honest about what my truck couldn't tow. They went from selling 5ers and TT's to just doing consignments and selling new and used parts. Last I read they were being sued for non payment from consignment sales.
The dealer where I bought our 1st TT from was overall honest. Yes they tried to sell me an expensive hitch but I knew it was overpriced. I was a good WDH though so thats a wash I guess. When we were looking we had a Nissan Frontier V6. I had really no idea if I could tow my 6500 lb rating. The salesman I worked with was honest and never tried to over sell me on a TT. However we went to the local RV show where that dealer has several TTs near the size I wanted. I happened to be looking at one that was a little bigger than what the original salesman showed me on their lot. The new salesman say yeah no problem with your Frontier. Well the sales manager happened to walk over at that moment and told us that no it's too big.
Had another positive feedback encounter at an out of town dealer. When I told him I wanted to stay within certain weights he replied that I must have a 3/4 ton, which I did.
And I've had some sales guys tell me that since I have a diesel I can tow some 36' 5th wheel that has a dry pin weight way over my payload ratings.
JMO but I think there's good ones and bad ones. I've had more good than bad.