What size diaper did your LO wear the longest?

Zee9635

My 7 week 9 pound baby is just now growing out of her XS dipes and into her small ones. I want to get her a custom pocket that only comes in sized, but I'm worried if I get a small she'll grow out of that soon and not get much use out of the fancy custom. If you used sized diapers, which size did your LO wear the longest? Should I skip small and get a medium she'll grow into eventually? Thanks!