Amazon offers 10% back in Amazon Rewards with the purchase of select HDTVs. (Rewards will automatically convert into a promotional code 35 days after your order ships.) Plus, all orders bag free shipping. That's tied with our mention from last week as among the best Rewards offers we've seen from Amazon, although we saw 15% back on select 4K UHD TVs during Black Friday week. The rewards expire after six months. A couple of best bets, with comparisons assuming you'll use the credit: Need it by Christmas? Select orders placed today are guaranteed for delivery. Orders placed via Prime by December 22 are guaranteed for Christmas delivery.