I have cruised 9x and have always taken insurance out. I have taken it out with RBC. I have taken full medical coverage and/or non medical. Sometimes the price difference between the two is only a few dollars to have full coverage (encase my work medical coverage doesn't cover it). Never know if you have a medical situation that you have to be air lifted off the ship (that only is about $15,000 or more), I have seen it done.
One cruise planned, my DH was layed off before the cruise and since I had coverage with RBC I was fully reimbursed.
Two years ago, we had planned on staying in Ft Lauderdale 1 day after cruise. When the ship docked in Ft Lauderdale we found out my mother was on her deathbed and we had to return early. All our expensives were reimbursed.
You NEVER know when something might go wrong,- missed plane, lost luggage, people have missed the ship while they visit a port, and covered after final payment to cruiseline. I have heard how people don't take out insurance (nothing is going to go wrong, we are healthy or too expensive and I will take my chance) and had to cancel at the last minute and want the cruiseline to reimburse them, which they DON'T. That is why you have insurance, it is peace of mind.
We are going to Disney World this summer, I am trying out President Choice's insurance.