For what it's worth, here are my thoughts on NCT.
We met some really nice people (which is why we did it), and it was a total godsend to have a group of Mums to meet up with when the babies were little. 4.5 years on, our group still meets up, although one by one people are drifting away from London.
We had a good teacher too, but as the NCT is heavily natural childbirth influenced, we naturally discussed natural childbirth more than procedures such as caesarians. I have heard reports from other mums on here that say their teachers never discussed medicalised procedures at all!
Also, depending on your area, I think the makeup of parents can be very varied. I met someone on our NCT course who had transferred over from another part of London as she found the other parents too different - she worked in the Arts, they all worked in the City. Our group was really mixed, artsy, teachers, civil servants etc.
We also attended classes at our local hospital which was very, very useful in terms of their policies, procedures, and good factual information on all the interventions and possible outcomes. For us this was ideal as we ultimately ended up having an emergency c-section.
So - NCT for meeting people and 'big picture stuff', hospital classes for the facts.
Sorry about the ultra long post.