I've used Denham quite a fair bit in both of my aeroplanes and have found the guys in tower and the instructors/office crew at Cabair very friendly and helpful regardless of whether I arrive in the beautiful polished one or the very tatty/distressed one!
However, £125/hr just seems a lot of money to me and I think that I'd would chose a flight school on something slightly more objective than the views. When you are learning you probably will not have time to appreciate those views, however picturesque they are!
That the instructors seem to wear airline pilot uniform is another thing altogether!
Not sure that this helps.
Stik