Thame is much much nicer to live in than Chinnor. If you have primary aged kids, there is loads going on that the school's all get involved in. A real sense of community if you want to join in. There is the annual carnival, duck race, music in the park, town music festival, towersey festival, food festival, literary festival, 10k run, fireworks, a small cinema, school events, plus many others, essentially if someone puts on an event, the whole town turn out!
Lea park ( where Roundhead drive is) is a big estate, approx 25/30% of people who live in Thame live in lea park. It's absolutely fine.
Lord bills is a good school, as said above almost all Thame kids go there, bar the few that take the 11+ and go to the Aylesbury grammars.
If you can, go and visit both areas, as they are quite different. If you want any more info on Thame pm me.