I agree that the branding for the shopping cart is very in favor of Amazon.com. But that will probably increase sales. I woul dlove to see some AB testing of a normal shop and the same shop on amazon to see who has the higher conversion. people trust Amazon because they know the name. I bet the Amazon store will have a high conv. rate.
The 7% & $60 mth includes CC charges nut it does not actually include the fullfillment. That is a seperate charge per item / pound / month.
Still overall a good deal if your margins are high enough.