I have the Norfolk Southern 21" excursion set.
Overall great passenger cars, very happy I bought them. QC was not bad, paint was applied well but there were minor scuffs . .
Interior is cheap and needs help, definitely worth painting and detailing
This is a fine example of what can be done with the raw material of the otherwise dull and unpopulated interiors of these ABS cars. I don't have one of the full dome cars, but based on what I have seen of them, the excellent sounds go some way to make up for the fact that everything that is visible through the windows is so plain.
There have been numerous threads on improving these cars, starting way back when @Alex M simply used rattle can and brush paints to color up the interiors of the original ESE set and put in passengers. But frankly, it's a kind of a never-ending challenge to make these cars live up to expectations or potential. The later runs of them, especially the UP Excursion cars, have more prototypical interiors - or at least some do. Best examples IMHO, from what I have, are the City of San Francisco dome observation car and the Business Cars.
I'm only showing what I have done with one of the latter, the Lone Star, to illustrate what can be done IF you are prepared to devote the time and add separately applied features. OK, I went hog wild on this, but the interior of the car is huge and cried out for detailing, without which much of the factory work is wasted.
I actually cut out and replaced a considerable number of the original one-piece molded parts to allow for what I decided to do, the idea being to create a car fit for railroad barons. In the end, it did not really come out that way, but it's my railroad and some whimsical elements got included.
This car has a forward section with kitchen, crew room and dining area and a rear section with an exercise room, staterooms, bathroom and an observation compartment. Both sections were modified to take out a number of molded-in features and substitute separately applied ones:
Skipping out all of the intermediate steps, the compartments were furnished and color and extra LED lighting (a lot) added:
In the end, the dining compartment got the biggest treatment, and in the observation section I mocked up (in acrylic putty with a flocked finish, which also went on the dining chairs) the vast serpentine sofa that was in the actual car at one stage:
To me, the kitchen turned out best of all, because - although it isn't a replica of the original - it tries to echo Pullman-Standard stainless steel diner kitchens of the classic streamliner era. The crew room got some no doubt un-prototypical creature comforts:
There are also exterior features added, including illuminated marker lights, modeling those that were installed on the car on a California excursion of yesteryear. I also substituted the 4014 Excursion badge in the stock drumhead, as best I could, but my mock-up of the GPS antenna on the roof is pretty crude (although all of the Excursion cars have something like this); the roof vent over the kitchen came out better:
At the end of this project, I decided that I was spending way too much time on customizing individual cars if I ever intended to finish a whole train. So I think that for the time being I will concentrate on cars that require much less upgrading.
P.S. @c.sam you have no lack of responses now!