We used Traditional Dining. We had no problems and the service was INCREDIBLE!!
Non-Formal nights "most" people still were dressed as if you were going out on the town. Guys had slacks with button down or Polo shirts.
If you have the money, we all LOVED the Helicopter Glacier Trek in Juneau!
We used room service once. They were fast and super courteous. No issues with the staterooms. Overall we had a GREAT TRIP!! SAPPHIRE was wonderful