I've never been to their Waterloo store but I have visited their Staples Corner one and bought online. They can be expensive as Dr Shoe pointed out I've overpaid for shoes from them. They have a reasonable range though and I think their clothing is very good, priced similar to other retailers and good quality.
I use their online store for corsets, it's impossible to get a good deal around here, and they've always been quick and discreet- never used them for shoes though.