Are we talking KNOTS or? My SVALBARD by www.eian.no have no problem hoding 4.5 - 5 knots. But that depends on the kayaker. The SVAKBARD dont have a skeg, but a rudder. The SVALBARD also have alot of volume, but its set as an expedition kayak...
http://climbing-and-sea-kayaking.blogspot.com/
pics.