Hi Frederick, I don't know about foamboards way of building. Probably it's possible with some extra work to keep everything strong and together. I've paddled this tandem kayak just in rivers, but on Danube river, sometime wind and waves are just like in sea. And all this kayaks performs very well. NoName is builded and paddled in England from Freedom Kayaks Ltd (under name Fulmar) in sea and reviews are good. I'm not so experienced paddler, but just have returned from Greece and there Anuket was exellent in sea with strong wind and rough weather for several days. So, yes - they are sea worthy.
Hi Frederick,