I am doing my PPL with them at present. Staff all seem friendly enough once they have gotten used to seeing your face around and the instructors seem excellent.
Aircraft availability seems good, it does get busy as said but they are quite good with their charging I find.
We were waiting about 10 or 15 minutes for take off clearance due to inbound traffic on one occasion but it wasn't included in my charge (although they describe their charges as chock to chock).
They operate a fantastic Chipmunk too for the tailwheel side of things!