A Sea Water Activated Release System was spec’d for all F-35 seats (US16E) if I recall correctly. perhaps that’s why it was also required on T6? As was a liferaft with a single skin canopy. (Although I believe UK MoD has (or is) changed it for something more useful in the North Atlantic in winter.) The F-35 survival kit was developed for a rapid re-role depending in which theatre of Ops it was to be used. Changing a liferaft type or scale of survival equipment was to be simple - by design - and it was, IMHO. However......
To quote a very senior member of MBA management, who commented to me a few years back:
“The customer will not always know what he needs, but he will always know what he wants...and he is always the customer.”
Look to the customer...