DD1 is a few years off secondary yet, but as we're expecting to move soon-ish (from York to Oxfordshire) we've been discussing schools. We're not really keen on private schools, so have decided to rule them out unless we have suitable no alternative.
However, at a recent Parent's Evening, the teacher suggested Grammar schooling, as she thinks DD1 - bright and academic, not particularly sporty/artistic/musical - will thrive in that sort of enviroment.
I'm not really asking about suggestions for good schools, because we're not 100% about the exact area we're moving to yet. However, we have no experience of the Grammar system - and so I've turned to the wisdom of the Mumsnet! 
So, to those of you that work at/have children at/went to a Grammar school... (And I appreciate that every school/child is different, so it's difficult to answer these questions.)
What are the pros/cons?
What do they offer that is significantly different to other types of schools?
Only a few things are putting me off. I'm worried about the pressure students are put under to achieve certain grades - while I of course want DD to try her best, I don't want her to feel like not getting a certain grade makes her a failure. I also worry about the lack of diversity, because I think school is a great place to interact with different types of people, which teacher children to be tolerance of different. Is this an issue with Grammar school, or am I just picking faults for no reason?
Sorry for the long OP. TIA for any replies :)