The CAA over a number of years made it clear that the pricing policy was to make the 'controlled environment' cheaper than 'controlled'.
By staying 'controlled' the annual revisit of airworthiness would be minised, so it was equivalent to the old Star - Annual - Annual - Star.
But what actually happened was that there is no benefit. The annual charge equates to the annual review, but by then many of us had signed to to a 3/4-year contract.
Worse, the CAMOs have different views of what they are doing. Ours have told us what we need to do (go to one of their subsidiaries) and when - no discussion. I've had 2 licenced engineers contradict our CAMO's view, but they won't listen, and I can't find another CAMO to take us on. So I'm stuffed. I either do what they say and get the ARC renewed, or I have a worthless pile of metal.
There was supposed to have been a change in rules post-July 2009 which means that sub-1000kg aircraft can have their ARC renewed by suitably qualified engineers. There are very few, as the CAA has made it impossible. The secret is to go Permit, as I wish I'd done