You can get the discount based on the amount of your DD points on the last phase when you must pay your order(redeem on top)
I know not a direct deal btw... you get also 1$ giftcard when you register
Most know DD, there are a lot of junks at higher prices (around the 90% of the items) but with coupon and gift cards you can find here also the lower price of an item
We discussed a lot of DD...
Recommended if you like the game(search a best buy the coupons and if something go wrong "play" with Customer Server, in that case I suggest live chat), them also ships fast
Avoid if you don't have time and don't want surprises.