I always bring a regular medium sized duffle bag and a diaper bag for my kids.
I'm using a Vera Bradley duffle bag for me and a baby/diaper bag for baby!
I pack my large roller bag that I use when I travel. I can fit everything in it. From my clothes, toiletries, baby stuff, pillow, nursing pillow & I have room for whatever the hospital gives me to take home & any gifts I receive while in the hospital.
I'm putting my stuff in a plastic bag and the babies in his diaper bag. I don't plan on bringing anything more than a pair or two of basketball shorts and shower stuff with my first I packed a duffle bag and didn't even touch half of the stuff in it.
I have a Vera Bradley, they always have great sales.