I opt for comfort as well. Currently, my only pair of shoes is an old pair of converse (traditional black); incredibly comfortable, but I fear lacking in support for an extended amount of walking. I will be trading them soon for a trusty pair of synthetic hiking boots (I am vegan, so leather shoes are out of the question).
I enjoy the feeling of flip-flops, though for some reason I find them somewhat displeasing on a purely aesthetic level (I cannot explain it). Perhaps I will find a good pair of hemp sandals somewhere.