Their CS is really great. However I ordered something a month or so ago and opted for two day delivery. Two days later the item still had not shipped and I called CS to complain. I was told that if they made any changes at that time to the shipping it would probably have an adverse effect on the delivery date due to where it was in the queue process, but they made a note to refund the ENTIRE shipping fee once the item shipped. They did refund my entire shipping fee a few days later. But since I've been at the top of the queue for 6 weeks or so (I ordered my KFire the day they were introduced) I hesitate to risk screwing that up. I think calling them after it ships is a safer way to handle it.