There appear to be two main types of shoes specifically geared towards formal Highland attire: the bar and buckle (mess) brogue vs. the buckle shoe. My super-polished black cap toe oxfords are great and can also be worn with a suit but I'm investigating other options. Ghille brogues are out of the question. I'm currently favouring the buckle shoe.

Is there any difference in formality between the two main styles (pictures below)? Are there other styles that I'm not aware of? What levels of formality are these shoes appropriate to? What is your preference?

I've been reading a few of the older threads about buckle shoes and found one that showed a DIY way of getting into a pair. The process is simply to acquire a pair of formal slip-on shoes and then attach buckles to them. Hopefully I can gather a few more details from the experts before starting this project and any advice would be much appreciated.

I have been looking on eBay at some fancier buckles made from iron or silver with patterns on them or else cut steel. The buckles I've seen from retailers, however, seem to be universally flat, shiney, and plain. Is there any problem with buckles that have a pattern on them?

Here are two images from our sponsor Keltoi Gaelic Clothing. I'm interested in cobbling together something like the first pair. The second pair is just for reference in any discussion.