My first baby was delivered by emergency c-section at st Thomas, and then I had a vbac at st Thomas' under mr mascarenhas earlier this year. I transferred to private care for last ten weeks of pregnancy, and then delivery etc. He was fantastic, quite matter of fact but knows what he's doing. The lansdell suite is nothing spectacular in itself but the on demand care was exactly what we wanted and, for me, worth every penny. Nothing was too much trouble
We ended up paying about 7k I think.
Personally I would go for private care at an nhs teaching hospital with everything there, as opposed to one of the maternity hospitals.
Good luck.