I have the medium tote and it's a more practical size ... you'll use it more often. I saw the pochette IRL and though it is really cute, it is very small ... definitely not enough for the junk I carry, I would use it for evenings out only.
I prefer the pochette! Although, it is pretty small.
I have one in brown but I don't use it very often because I like to carry around lotsa things with me so if your like me, you might wanna consider getting the tote.