I work for Celtic West at Exeter Airport and along with Exeter Flying Club provide the only PPL training at EXT (Airways Flight Training provide advanced courses - IR etc).
Our prices (£105-C172, £97-C150) are very similar to Exeter Flying Club, and to be fair it really is a case of visiting the two to see for yourself. They are more of a club with bar facilities etc whereas we have more experience with the commercial side of things - charter work and a recent daily flight from EXT to LGW for BEA - and more news in the pipeline.
Hope this helps.