It's surprising how well these ships sail; although square sails are often thought of as only being effective going down wind, they sail somewhat into the wind fine. And of course, you don't have to worry about a bad gybe removing your rigging.
I was in Norway a few years back and took a tourist trip in a 2/3 replica of a Viking boat found in a burial mound - the crew took us up the lake, turned round and came straight back - it was remarkably nippy and seemed to handle very well. I'd be interested to read how the much larger ship here performed under sail.