I saw the play and enjoyed it. Both Ben Wishaw and Judi Dench were fantastic in their roles and I thought their experience in growing up with such inherited fame because of their names was beautifully expressed, in the different ways they lived through it. You could feel in particular that Peter was still very troubled by it and found it hard to shake the ghosts of the past (also very well portrayed by actors appearing as Peter Pan (not as a Disney version, thankfully), Alice, Dodgson and Barrie.
I wasn't sure however that anyone without a previous knowledge of the lives of the Llewelyn Davies boys and Alice Liddell would have understood the psychological turmoil experienced by them.
There was another post about this play a while back in this forum, which might also interest you.
I'd be interested to know what you think after you've read the script, as that would be quite a different experience from seeing it staged.