Well first off the boxcars in RS were quite poorly done in terms of scale and prototypical accuracy, they are well detailed but look wrong for a variety of reasons. Im guessing in this case though its because of the FOV, RS has a somewhat wider FOV than trainz so i think that may be the reason.
you'd think box cars they would at least get right... they can't be that hard to build.... they are a box on wheels.
peter