Had the set for our first holiday (our little girl is 10 months) bought. Can only say positive. the zip is long enough to ensure easy on and off. The lock is protected by inner neoprene insert. Since the shell is a little longer, could slip anything even when crawling through the sand. Personally, I find the set more practical than a one piece, because you can take off the panties when getting wet very quickly, but then protected by the shell still is (or it may sometimes wear separately).