I'm basically of the same opinion as Osseous... They're nice, but I fear for flexibility. I have rowed one; a very early version that a friend bot for his shop. It was OK, but didn't really make me twitterpated.
Either will fit you, you should be able to adjust all that's necessary. You really want to size the boat to the task, not the person. If you are fishing two folks, non stop and rarely varying the smaller would do fine. If you ever want to go with 3 folks and more gear the bigger one will be WAY more useful. It'll float higher with the same load and carry bigger loads. 6" length and width really isn't that much when it comes to fitting the boat anywhere but drastically different in capacity. It'd be a no brainer for me, but then I just jumped from 13' to 15'.
Yesterday's gone on down the river and you can't get it back. - Agustus McCrae