For the website it was really easy to navigate around and the range of options you could filter between was a large amount, you could find what you was looking for easily.
However they did mix both underwear and lounge wear together on the website as well as in store, so this does make it look a little bit jumbled.
The size guide on Topshop's section, has quite limited sizes, only going up to a 36D, where as I have friends with 34EE, who are petite in there body size's, so they sometimes struggle to shop through Topshop's section.