I have a 9 and a I think a 14 or 15. The 9 gets a lot of use. I see you are a Petit gourmet. You need to be strong to lift either of those two. :)
I use them for all kinds of braising. When I braise, make soup or chili, sloppy joes, etc., I like to make a lot of food for leftovers, and both those pans make that possible. The 5 quart seems awfully small to me.
They are expensive, though. I bought mine at an outlet store in Kenosha, WI and did well I think. You have to check them closely for imperfections in the enamel. The person working at the store checked them very carefully with me and we went through a few of them before we decided. They are very helpful there.