The Food Chain!
If you are in the "food chain" as a Mess Member and have any choice in whether to move to PAYD then say no! The company may not offer more expensive bar prices initially, they will creep up over the coming months! The choice of food at the counter will start off looking like a good selection until the mess members decide that eating is better and cheaper elsewhere, and then the food choice and standard will decline! Any priveliges that you think you had as a mess member, like getting the mess to cater a private function for you at a "brilliant" price and a bottle of scotch will go out of the window - expect to pay high street prices if you can afford to use the Mess's Catering Company!
The whole affair is yet another degradation of the priveliges and standards that we used to enjoy living in an Officers' Mess or a Wardroom.
Another one of the reasons that I have chosen to PVR from the RN after 27 years!