This is the best way to spend another gift card on Amazon. I had a $100 Visa gift card. I wanted to order $122 worth of stuff. If I had processed it with my Visa gift card it would have gone through then later some of my orders would be cancelled. By buying this (at not extra charge) you can use more than one payment method up front. You have to work around Amazon's limitations.
At Target for example, if you give them any gift card, they know the balance immediately and subtract it allowing a second payment method. Amazon however, doesn't have that technology. This is a great workaround.