Interesting precedent.
The "latest" requirements for Crash Worthy Fuel Systems outlined in Part 27 - 952 have been in place since 1994 (23 years).
Air Methods knowingly operated a product which the manufacturer used a "grandfather" clause to avoid installing a CWFS.
The manufacturer, by means of offering a CWFS retrofit will certainly reduce it's liability for future accidents.
The operator on the other hand.....
And what about Part 27 - 561? It's been there since 1994 and was likely a contributor to the death of pilot Pat Mahany.