I think that it is more the look from the front than the actual joinery. I just like the look on the left (with or without a rabbet) better than the right. I guess that it is the miter joint itself and it could just be the drawing that makes it stand out and in real wood that probably won't bother me as much. I do like the contrasting splines.
--Nathan, TX. Hire the lazy man. He may not do as much work but that's because he will find a better way.
