Jayco, what does the dealer know that I don't know?

Both Jayco dealers here in the Salt Lake City area have tried talking us out of a Jayco, and to go with a Montana or Cougar instead. I'm just wondering why. Our first trailer was a brand new 2003 Jayco bumper pull and we loved it. I really wish we had kept it, but wanted to try the toy hauler route. We now want to go to a fifth wheel with slides. We liked our Jayco so much, maybe because it was our first, I don't know, but we really have our hearts set on going back to a Jayco. We are open to other brands, but cannot find another that has the large capacity fresh water tank or floor plan we like as much as the Jayco's, but even the Jayco dealer talks them down and keeps pushing the Keystone trailers. I'm sure Keystone is also a good brand, but why do we need a 90 gallon black tank when our fresh water tank is only 64 gallons? Is there something the dealers know that we don't as far as Jayco fifth wheels or slides?