I hadn't considered NOT wearing my mini-medals in the formal attire. I earned them and the only reason they are not listed on the invite is that it is a civililian affair, having nothing to do with the military, just like our local Burns Supper.
Ah, but Burns himself served in the military -- the Dumfries Volunteers, the local militia unit, and was a very active member:

http://www.btinternet.com/~james.mckay/disp_002.htm

And many Burns Suppers do invite ex-servicemen to wear medals and decorations, regardless of whether it is a "civilian" event or not.

Regards,

Todd