Agreed. AMEX really goes to bat for you. The few times I have had an issue they go after the issue with tenacity. No hassle to me beyond a 2 min phone call.
I had the opposite experience: the one time I've tried to use this with Amex they were completely useless. We had a fraudulent $200 charge on our business card, and Amex ruled in the merchant's favor after being presented with an unsigned PDF "receipt" that was nothing but the text "Digital Software... $200"