I had trouble with them falling out. My ears aren't small, but this model's shape, size, and smooth finish made them pop out constantly.
My experience is mine and you will have a different ear shape that might be better but you'll have to try on your own.
They do come with 3 sizes of plugs that can help get the best possible fit but I couldn't get a stable fit!
I ended up with the older Buds+ which have "winglets/tabs" to help hold them in the ear.