Another factor, besides those named (which are true), is that it is likely that the previous low bidder may have their "plates full" of other projects and simply could not build the cars when and how RT required.

I've seen companies not bid or bid "too high" because they did not want the project, but felt that they should be interested for the sake of future projects.

I personnaly like the Siemans cars much better, except for the doors and the railings.

I'd like them both BETTER if they weren't so danged cold all the time!