I sent one of my shots to the same critiquer (my long time mentor and close friend). He sent it back cropped as a vertical, saying that gave it much more impact. It was a head-slapping moment for me since I quite agreed with him. Since 75% of my final prints end up as verticals, I was surprised that I had not thought of that while shooting. Then I recalled that I was concentrating on capturing the afterglow of the sunset behind the extended mountain range with the snow in the foreground and that normally requires a landscape mode. The teaching point here is to not get so locked in on the subject that you miss seeing a better perspective. Again, which one do you prefer?