Just for kicks, Larry, I have looked at it too and found that with our options, the difference would be about 100K in our same layout (4018). And the heck of it is that it looks to me that it would be worth the difference if you really wanted to spend it!
We looked at an MA at the Tampa Show with a sticker of $488K -- one guy who happened to be on it and seemed to know a fair amount about these things said that he was persuaded that the Mountain Aire was the absolute best value of all Newmar products for 2013 vis-a-vis quality and features. I wondered ...
I am interested in your post -- would love to see the actual Order Sheet to see how close I was in my calculations.
That being said, we are really over the moon with our '13 Dutch Star!
Deek