It all depends on what you want to do and where you want to go - they do suggest what the dress should be for that night but you do not feel left out if you do not want to dress up. We went to one of the formal restuarants and decided to dress up but it was not a formal night but did not feel out of place. So if you are going for a week you will get 2 formal nights.
We cruised transalatic Sea Princess and had four formal nights The Kilt is accepted and grately admired however transporting your SkeanDhu can be to say the least a problem in this climate of bad people. For ladies I just wore cocktail style but wish I had chosen something to wear with Clan tartan stole to compliment the kilt. Enjoy your trip. Lynne Macpherson Ullapoo.