DS1 is nearly 8 and still in a high backed booster. He's 7cm off 135cm and I would say his friends tend to be a similar height.
Now when I've collected his friends they have all commented on the seats. I get the impression that most of them don't use them anymore. They say their little brothers and sisters do so its not families who totally ignore the law. I was just wondering how many people actually stick to the rules properly?