I think those shirts would look great with a kilt (not the Black Watch one, obviously, but one of the solid colors). It has an historic flair to it, but it can still function as a modern shirt, so you can wear it with the kilt without feeling like you were in a costume.

I may just add that to my Christmas wish list! Have you got any photos of you in that style, Ron? What is your opinion of the fit and quality?