We live in Surrey and there area and there are a few very good Grammer schools round here. My son has just started reception so we are hoping to make the move to an indie school in January. I am aware that some of them do not prepare them for the 11+ so I will have to do the work with him or use a tutor, closer to the time.
As you are aware that you might have to do the work your self, the choice should not be too difficult. My earlier comments were made based on our experience as that is the selling point of the prep school our son went to. They tell parents that all work is done by them & not to worry about tutors but that has changed now as parents have realized that is just a sales pitch.