The one complaint I've got is the cursory way they check DS. We've had 2 dentists since we moved and will soon be on our third, and they all just quickly peep in there as if to make sure that he has teeth at all! I personally think that at age 11 it's past time for the first cleaning but as he's NHS I don't think they want to do it.
I have had the exact same feeling about my kids. The children's dentist that we loved and trusted in the US told me that my son's permanent molars were coming in with a bad problem because of something that happened prenatally. He said that when they came in they would have no enamel and would have to be watched very closely.
Then we moved over here and I took my son to two different dentists (after the molars had come in) and they just counted his teeth and said he was fine. Well I could
see that he wasn't fine! The brand new molars were horribly misshapen and discolored. The second dentist did take x-rays and give us an extra fluoride toothpaste. Then she had him back for a second appt. which I assumed would address the problem. Instead she had a talk with us about his diet (if she'd asked in the first place she would have known it was excellent) and she showed him how to brush - for £40! Well he'd never had a problem with brushing, which I helped him with, so that seemed unnecessary. She told us just to come back if he got a toothache.
I was very suspicious because I felt she was ignoring a serious problem. When we went back to the states for a vacation (in a different state than our original dentist) I made an appt for my son to see another dentist. This was three months after the British dentist. They said the tooth decay was so bad in my son's molars they would have to be crowned at once and that if we'd waited any longer he would have needed root canals! If we'd waited for a toothache like the British dentist said it would have been too late.
My daughter has never had any trouble with her teeth but I took her to the US dentist too. They said she was fine and just keep up the good brushing. When they told me that I believed them because I felt I could trust them.
After my experiences I just don't know if I trust the British dentists. They seem to have a casual "we don't treat it unless something goes wrong" approach. I've never been too fixated on perfectly straight white teeth, but I've kept up with preventative care and don't want to end up with a head full of crowns and root canals like my husband has any earlier than I have to. My husband is adamant that he doesn't want that for his kids either.