I really like my all in one kushies, much quicker and easier to put on and handier to wash than seperates, less bulky for toddlers walking and can be stuffed for extra absorbancy if required.  Comes in various colours so can be really attractive.  Very useful for at the toilet training stage, my daughter is currently learning to be dry overnight and they are really good for this as without a booster they are light and cosy but still absorbant enough for any accidents.