FYI
In December I got a platinum and canceled w/in 30 days and got the full refund.
I had 2 lounge experiences: During the 30 days that my card was still active I got denied entry into the united rcc in chicago. They have a sign that they don't take it anymore. After I had canceled it, I got in to the China Airlines lounge with my wife (i was flying cathay pacific in the same terminal). They just swiped it and wrote down something and let me in.