There's a line in a Tom Petty song that always makes me think of Merlin:
"
While we celebrate mediocrity, all the boys upstairs want to see
How much you'll pay for what you used to get for free..."
I'm not convinced that being 'good value for money' and simply 'being cheaper than visiting without an AP' are the same thing.
The AP remains cheaper than a single visit to each major attraction across a year, and would certainly save money for anyone intending to visit the London attractions or who has a fondness for Sealife centres (worth pointing out that aside from London and arguably Birmingham, non-Merlin aquariums are better and more varied). However, this is only because of the ludicrous on-the-day prices across most, if not all of their attractions. Therefore, it may seem good value for money, when as an overall product, this is far from the case.
I know what I'm trying to say, but it's proving hard to put that point into coherent words. While my interest in theme parks has certainly had a resurgence in the last twelve months or so, a MAP would not have been a good investment for me this year - the only thing I miss is being able to go to Alton on a whim, and to be honest, my last trip there left me with little desire to return.
There's also the point that it's become progressively worse value over the decade or so whilst Merlin have tightened their ruthless stranglehold on the UK's entertainment industry, but others have already gone into this