The Expedition Single is a very large boat. You are not too large for any of the Guillemot designs, save maybe the "S." You are the specified weight for most of them.

Stability is not solely related to the beam width. There are so many variables- but if you're coming from a rec boat background keep in mind that length has an effect on stability as well as width. A 20" rec boat may be unstable compared to one with a 28" beam, but if you add 6 to 10 FEET to the rec boat (which would put it in the range of most sea kayaks) it will become much more stable at 20".

As to stability- if you stay a beginner forever stability should be your main concern. However, you will only be a beginner for part of one season. If you build a boat design chosen on stability alone, you will be disappointed very quickly. If you build a boat for the conditions and use you intend for it, you'll be much better off in the long run even if it feels tippy for 4-5 weeks.

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