My friend tried if her pochette wallet could fit in my pochette, and it does. It's not jammed in there, there is enough room, but you can't put anything else in it. That's why I think I'm gonna buy the new zippy coin purse, because I do want to carry other items with me.
I am able to fit a Ludlow in the pochette along with a cles and cell phone. I think the Ludlow is best since it is lightweight and relatively slim. With those items in the pochette, I am able to fit a few lipglosses/lipsticks, mints/gum, as well. I don't like to weigh the pochette down.