RedPanEd, those tank volumes peaked my interest. We had a 1996 190P on the Dodge chassis (probably the most enjoyable rv we ever have owned) and I didn't remember tank sizes that large. So......I dug out my old brochure for our 1996 and sure enough, the tanks were smaller in 96 than they were in 99. Roadtrek was constantly fiddling with "stuff" back in those years, making small but great improvements in a lot of things every year or two.
Our tanks were 35 gas, 31 fresh, 25 gray, 12 black. On our 2007 RT 210P they are
31 gas, 30 fresh, 23 gray and 10 black. All smaller. That extra 20% (from 10 to 12) black
is significant when boondocking.
The lesson for me is never assume anything! Look up the stats. Thanks for your post.