Thanks for the responses toquehead
. We've been away over January, camping and kayaking among other things. At this stage I've fitted a couple of Railblaza star ports to my kayak, just in front of the cockpit and have been using a Railblaza camera mount kit for either my Contour Roam or Olympus Tough 4G cameras.
I was a little disappointed about the loose fit of the camera adapter in the star port (it wobbles slightly), but it doesn't seem to have affect video quality (very few sudden jerky movements). A thin shim of plastic would probably solve this issue, but knowing me I'd lose the shims regularly