You are and you aren't. The way AMEX does this is if your product is eligible for warranty repair (you didn't drop them in the toilet) then AMEX refunds the full purchase price. They are supposed to ask for the product to be shipped to them but they haven't done this (that I've heard) in many, many years. So you just end up keeping the product and getting a new replacement or have the old ones repaired on your on.
I have a friend that had three iPhone 5 have button issues and he got full refunds on all of them. They were AT&T contract so his full refund was $400 each. He ended up taking them to a shop to get them fixed for cheap.
I use AMEX for all my purchases because of their great benefits.
FYI you are NOT covered for AMEX warranty. Item has to be paid in full in order to qualify for extended warranty, purchase protection, etc.