Scott,

The comments in posts #24 & #26 say it all. Who do you want to impress - your wonderful Wife I suspect! I suggest that you ask her. Having had tea or coffee in both the Balmoral (North British to those of us who remember it) and the Scotsman I suggest that you will do just fine in shirt and tie or sweater or tweed jacket.

Be comfortable and soak up the admiring glances.

I hope that you have a fantastic trip to Scotland.

Peter