Ok, I lied, I will enter part of the saga....
I don't like the combo tank because for starters I don't go to full serv all the time when I go camping. I use/fill more gray water than black. I'd say easily 2gals of gray for every 1 black. So what happens if the tank overflows. Well, I get black water mixed in with the gray. Where as now, I might only get my soggy corn pops back in the shower...
Now at the rustic spots I go to, I can let my gray water run straight out if I want to. If I had a combo tank, I'd have to hold all that extra water weight until I could find a dump station. Now on my way back from Louisville home, there were no sanitary stations at any of the rest areas on I-65. So I would have to have hauled it all the way home as I did my 1/4 full black tank on my dual tank Bambi. If I had a seperate tank like the rest of the Airstreams (of similar size), I would have easily lost about 330lbs by purging the gray tank (8.6lbs per gallon I think is the weight of a gallon of water).
That's my main concern(s). For those a full serv campsites, not an issue I agree.
Given the size of the trailer though, I can't seem to understand why they would consider that unless they did some market research or something.
Eric