Smilyjo, I know a bit of what you are going through in that they thought my DD had craniosynostosis. This wasn't picked up until she failed her 8 month development check and then we had the wait of being referred to Great Ormond Street Hospital, them losing her notes, being referred again. Once she was assessed at GOSH they told me that DD doesn't have craniosynostosis. With my DD2 they thought she had unilateral craniosynostosis where the plates at one side of her head have fused together, the plate in front of her left ear. The reason the Consultant came to the conclusion she didn't have this unilateral craniosynostosis is because, unlike your daughter, it was not really picked up on until she was about 8 months old. I noticed at about 5 months of age her head was rather "odd shaped" but when I saw the doctor she told me it was nothing to worry about. It was only when we were referred to our local hospital for delayed development (fine and motor skills) that they picked up on her funny head shape and decided to refer us to GOSH after having spine and skull x-rays that came back with the opinion that "synostosis could not be ruled out".
When this was first going on, I looked at varoius web-sites (most of them american hospital sites advertising their skils, expertise) and got a lot of comfort from seeing children pre- and post-operative.
When I thought about DD having to have the operation, although I was worried about it, I know I would have gone ahead, even if purely for cosmetic reasons, as everyone wants their child to have an easy a life as possible and not being teased, and we all know how critical children can be about other children. Obviously if the operation is required for more serious reasons, pressure on the brain, etc. then the decision would have been taken out of my hands.
Even now DD still has a fairly lop-sided shaped head (although only noticeable when looked down on, rather than face on) but to me she is no different than my other two children, she is still as beautiful and absolutely wonderful.