Ready - I'm no insurance expert, but I believe a either insurer could either directly pay the medical facility or the insured. Many US employer's health policies do not provide coverage when traveling internationally (unless for business purposes.) That, plus the cost of items such as medical evacuation and cancellation issues.
All I ask is a tall ship and a star to steer her by; John Masefield
Carnival: Glory 2004, Destiny 2008, Splendor 2009, Freedom 2011, Valor 2012, Dream 2013
Celebrity: Summit 2011
Princess: Ruby 2010, 2014, Caribbean 2013, Coral 2014, Regal 2014
Star Clippers: Royal Clipper 2015