My wife and I just completed an 8 day 7 night cruise on Windstar's Wind Surf. What an incredible performance by the entire crew. This is the easiest boarding experience of the many cruises we have taken.
We were actually greeted by Captain Harris as we embarked. The Wind Surf is essentially a large yacht, which is engine powered but that also raises it gorgeous sails. When it departs a port, it plays "1492", which is very cool when your sitting on the aft deck of the yacht watching the departure, sipping a drink.
The yacht is classy and understated. You can tell that everything is finely made, but not overstated or gaudy in its decoration.