Had to cancel a flight this morning on account of a wet runway at EYW, and I’m a little confused on the difference between FAA approved and Manufacturer approved with regard to landing distance tables. Prior to the issuance of the supplemental landing distance charts for the Beechjet 400a there was no contaminated runway values published. This supplement for take off and landing charts only has a manufacturer approval and not FAA. My question is are these numbers binding? If not and you elect to go contrary to what these numbers say do you chance having your insurance not cover and accident should you land long or could you be found in violation of the of the regs by not adhering to a manufacturers recommendation? If this is the case, we Beechjet drivers are going to have a difficult time flying anytime there is rain or snow on anything less then 7000ft. Thanks for any insight anyone might have.