don't order a ton of 0-3 in any brand....maybe a few just to get you through.
you're LO will likely grow out of it quickly.
i'd wait and order more in bigger sizes like 3-6 or even 6-9 so they will enjoy it more. the first couple months they should just be comfy anyway - thye don't need jeans and outfits
carters has GREAT sleepers - and probably half the price than GAP