I have ordered 2 large orders from Cotton On and I have always been happy with the products except for 1 item being too small, for which a quick refund was given and 1 item which just didn't suit me (my own fault) all have been great quality, and here in New Zealand you can go into the store and swap sizes if you need to.
Overall, great website to shop from with awesome sales prices and variety, I will definitely be ordering from here again!