I usually pay my credit card balances off in full every month.  I have never made a late payment to AAdvantage or any other card.  One month I had to leave a $1500 balance on this card (around tax time) and thought, oh well, 13.24% on $1500 is only about $17.00 for the month, no big deal.  I paid off the balance in full the next month. They charged me a total of $87.88 in interest over 2 months for leaving this balance of $1500 for one month.

That is actually somewhere around 65% interest.  This company is a lying, cheating, den of thieves.  If you don't want to get ripped off, stay away....