Join Date: Sep 2005
Location: Lafayette, CO, USA
Programs: SPG Lifetime Plat, AA Gold, UA Gold, DL Silver, HH Gold, Vail Epic
Posts: 9,096
You might be better off using a coupon code. Or depending on how you value a mile, you might prefer cash back. In some cases, you might can use both. (check fatwallet.com). And FWIW, UA gives 3 miles per dollar whereas US only gives 2.
If you are building your own ring, a coupon code will only apply to the setting -- not to the loose diamond.