I can only echo what Bob and Luca have both said, never had any problems with Amazon and my wife buys stuff on a regular basis from them without any hiccups.
I have bought on some occasions from their 3rd party sellers but again you would never know, always had excellent services. I think they may even run a feedback rating a little like Ebay.
If you want to edit any of my images to demonstrate points/techniques to either myself or others please feel free to do so.
Still learning with Canon 40D, 28-135mm, 100-400mm L and Elements 6.
Any Advice greatfully received.