"You are correct. For some reason, the one "on the right" is what catches my eye."

Interesting. Before looking more closely, the one on the right looked marginally better to me as well. Assuming it held up in further tests, it might have something to do with eye dominance. My left eye is better than the right, so it's not better acuity - for me at least. Stacking them vertically is left as an exercise for the reader. The moral may be that in a competition, try to get your image on the right :-)

"Democracy is a pathetic belief in the collective wisdom of individual ignorance." - H. L. Mencken