I bought the large and it is well and truly big enough for my newborn and toddler items. The bag is absolutely beautiful but the material has a strong smell which took some time to rid of.
Reasons I've given it a 3 star:
Given the size and capacity of the bag, I expected more robust straps. The adjustable straps also moves easily as you carry them as a backpack which is annoying. Furthermore the bag doesn't stay on the back when carried as a backpack.