My recent experience is actually with the Citi Prestige Card, but I would not be surprised if the same insurer is used for claims for both cards.

I've used Amex's return protection policy a handful of times, and even when I have been asked to return the item, it has been fairly hassle free.

I submitted a return protection claim with Citi for a $39.99 computer mouse SEVEN weeks ago and am still waiting for a decision from the insurer. I have followed up twice via phone and once via e-mail (someone from the insurer actually e-mailed me a few weeks ago to apologize for the delay and to tell me I should hear something soon), but all I've been told is that they are "expediting" the claim due to the delay and I should hear back shortly. (Of course, that was what I was told after four weeks had passed.)

Needless to say, compared to Amex, I am not impressed.