AmEx Blue is a credit card that they offer. One of the benefits is the Best Value Guarentee Program. It's awesome and it really does work.
That program and some others.
Return Protection
Return Protection lets you return a covered item purchased with the Card [ even if you purchased it...
If you get the AmEx Blue card, you can buy it from 6ave.com (an authorized dealer) for $599 plus shipping, and then pricematch to $500 (one of the shady internet dealers).
Aaron