After viewing the numerous pictures of everybodys wonderful looking machines, I have a question that some of you may be able to answer for me. In the designs that use gantrys with THK type rails, is there some kind of advantage to how the rails are mounted. I have seen types where the rails are mounted flat on a plate and the plate is orientated in a vertical plane. The other style that I've seen is where a square column is used and one rail is mounted in a vertical plane (side) and the other rail is mounted in a horizontal plane (top). Could this be a personal preferance or is there some rhyme to this reason? Please comment. Thanks in advance.