I know where the OP is coming from. Seems like La Mesa different locations are as different as night and day. We've always had super service from Tucson, either on warranty or pay service. Parts and sales go out of their way to help. I had Phoenix flat out lie to me and when I called them on it, they would no longer even talk to me about warranty work. Yuma was generally unresponsive in sales and repair. Quartzsite sales good but I've had no dealings with their service.
Never know what you'll get, except for Tucson. They are one of only 3 places I'd take my Tiffin to in the US.