As a paddler I have seem many schools of thought when it comes to sizing a boat. I seem to have narrow it down to three main ideas.
1. Go with the kayak manufacturer's weight suggestion.
2. If you are a big guy, buy big even if you aren't aren't suggested weight range.
3. If you go big, buy big (creek). If you throw big, by small (play).
I have always found myself sticking with the manufacturer suggestion by placing myself in the middle of the suggest range. How do you size your boats?