There is new Amex Offer through July 30, 2014. You will get one-time $10 statement credit when you spend the total of $200 or more on American Express Gift Card. The offer is available online only, www.americanexpress.com/gift-cards.
I have two American Express cards for Amex Offer. One is Blue Cash Preferred, and the other is Serve. However, you can’t use Serve for the purchase of AmEx GCs. They don’t accept Prepaid Cards as a payment.
Please don’t forget to click a link of shopping portal. As of July 1st 2014, the best rate is BeFrugal’s 3% cash back. Once the rate was down to 2.5%, but it slightly went back up.