Well Ultra to answer your question(s). Yes, I like the "Coat It" product, but be careful when working with it. It starts out a little watery, stays that way for a while, then really starts to thicken up fast. Ask a friend to help, you'll be glad you did. Secondly, a gallon will be enough to do your boat and probably a friend's boat too. I used a quart (just right) on the seams and rivets because of a post I received on this blog that said "Why coat the whole boat, when only the rivets and seams are gonna leak. If you leak somewhere else, you've got bigger problems!" I hope this helps you.
Moccasin Don, we used Rustoleum "Top Side" paint on both the interior and exterior. I think it comes in four colors. Just be sure to use a good "self etching" primer and scuff up the primer and paint before the next coat. We put two coats on the outside using a roller. It dried real smooth, I was surprised/pleased at how well it turned out.
Thanks to this website and its members, we got alot of great advise. We "Stole Shamelessly" and built a boat we will hopefully be able to enjoy for many years. I hope that others can use some of the successes AND failures from our build to do their own. I have had a great time working on this project with my boys and have met some great people along the way. I still have a couple of things I want to do, so look out for more posts as we button her up before the start of next season. Particularly the electrical stuff.