I'm a beginner and I've built these two 13' SOF's for my wife and I. They are inspired by Tom Yost's Sea Tour 15 but are considerably wider at 31 inches. Comparing them with the behavior of plastic boats I paddle around in the reservoir near my house I'd say they perform quite well and are very stable.
The Red Boat
https://lh5.googleusercontent.com/-f6TMSl0XiDk/Th_kPl13S6I/AAAAAAAAALg/gWUma89UhRU/s800/IMG256.jpgThe Blue Boat
https://lh3.googleusercontent.com/-g36TwbzP15I/Th_vsjJ1-II/AAAAAAAAAL4/EKqoCnhU3MY/s800/DSCN1285.JPG