For what it is worth we have had a very positive experience with La Mesa RV in Tucson. I went in to buy our Nexus Class C after it popped up on the internet. I was satisfied with the deal we negotiated, got exactly what I wanted at a good price, they treated us well and made money.
Their service department has been excellent on the two occasions we used them, one being to clean up after Camping Worlds botched attempt to repair our water heater. I went in initially prepared to be disappointed and/or frustrated with the buying/service experience and was pleasantly surprised.
:C