We've taken both the Anguilla ferry service from Marigot and a private charter service, GB Express from Simpson Bay many times and have never experienced rough seas. I'm pretty good on water but DH not so much on occasion. Have we been lucky? Maybe. But it is a channel of open water between the two islands and unless the 'Northern Swells '( I don't know exactly what that means beyond high and rough seas but I like the way it sounds....) are running, the crossing is generally no where near similar to the sail out to StB or Saba.
Most people will be fine. If in doubt, sit outside or near a window and focus on a fixed horizon. This seems to help some who have issues, and of course there's always wristbands or patches. I personally wouldn't take Dramamine or Bomine because they should limit your drink experiences on the island and at least one of them might make you drowsy. But like I said, we generallybhave nonissues and I would NOT waste the money to fly over. <img src="http://www.traveltalkonline.com/forums/images/graemlins/handshake.gif" alt="" /> <img src="http://www.traveltalkonline.com/forums/images/graemlins/handshake.gif" alt="" />
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