Rick, I finally got one after Countrywide went under a few years ago. They always gave double the $$ credit that Princess was offering but now Princess is as good as you can get. I don't know about the percentage rate they charge for unpaid balances since we never have one but they don't charge anything to have the card.
What is nice is when you charge your Princess cruise on it you get double points. We usually acquire at least $100 in cabin credit 4 times yearly. Some people do charge much more but we're not big spenders.