Thanks for taking the time to reply. Really useful feedback.
I think next step seems to be to just try at each school and see which one I get the best impression from along with the other logistical factors - what other things should I be looking out for?
Or should I just start somewhere without making it obvious I'm "in the market" choosing between schools so I get a representative experience?
Denham is the most convenient probably so if it seems good there it could be a great option.