I have had nothing but positive experiences with Amazon. I often get their 2-day delivery. When an item was delivered late, they did not charge me for the item.
I pre-ordered a season of Dexter at a cost of $40. By the time the DVD was available and ready to be shipped, the price went to $18 and that is what Amazon charged me.
I am on their monthly subscription to receive organic Japanese green tea. It is less expensive through Amazon, even including the shipping, and the tea is left on my doorstep every month