I am not a big pen buyer because I don’t sit at a desk with pens all neatly arranged in front of me. I use them on the fly, scrabble for them in my bag, use the cheap promotional ones workplaces usually have and then lose them.
For this smaller size binder though, I have been using my three smal Filofax pens and loving them. The Touch Me pen loops are half-elasticated and so pens fit in there nicely. To be honest, they are a little scratchy for my liking but they work well for the few words I need them to write and they are so pretty!