There's more to this than just the cost - I started at Teesside and rapidly got fed up of the drive from Newcastle there and back for a cost saving of about £10 an hour. To be honest it seemed worth it to avoid the 1 hour drive each way as I live 15 minutes from EGNT. All sorts of ways to shave costs at Carlisle incuding doubling up to share flights - also very sociable! I think the arrangement is that there is 1 landing fee for as many circuits as you want - plus your nav there and back is never wasted so I really don't see it as a problem.