In the interests of MN research I went into River Island this morning. OMG - it was horrible.
The girls' clothes were awful. Really trashy - I wouldn't let my dd wear those sort of things.
And the adult clothes soooo expensive, given that they are aimed at "youngsters". £28 for a shirt, and £60 for a very obviously faux leather jacket made of polyester. Those are not teenager prices. (Well, they are if you're a Hollister/Jack Wills fan, but not for the average teen girl wanting some new togs.)
When I was a teenager, I used to go in Chelsea Girl and then River Island all the time. Now I'd go in H&M or somesuch which has much better stuff at certainly a much better price point.