The chance that there is someone who used those specific parts is pretty small but there will be people who have real world experience with Shapeways
I have an impression (positive) from the posts I have seen here, but you shouldn’t make a decision on the memory of my impression, especially since it is only on the edge of my radar screen.
You could also search Shapeways in the box on the right, midway down this page.
I recall a Youtube video on a guy who used Shapeways to constuct a side dumping gondola or ore car. I cannot find it on a search, it was probably a layout tour from a 3rd party. Anyway there was a lot of detail. The detail depends on who does the CAD work for the model.
Whatever the detail, the quality of the 3D printing is up to Shapeways.
I bought an HOn30 boxcab body from Shapeways last year from a different Shapeways store vendor. I was pleased with the results. I posted this about the build (sorry about the photos not showing, I have not transferred those images off Photobucket yet)
Look at the feedback and reviews about the guy who designed the caboose parts.
You should do a bit of research on Shapeways about materials, there usually are a few to choose from at different prices. Part of it is ‘you get what you pay for’. In this case the more expensive the material, the better the quality of the finish. I used Frosted Detail, and this was accepable to me.