Discover are very easy to work out issues.  We've had charges made to our account in the past that were not our, or the request from the vendor was not satisfied.  Discover took care of the dispute without putting more burden on us.

There was another time where I had accidentally applied my payment online to our 2nd Discover account and when I received my bill the next month they had a late fee and finance charge on the account.  After we investigated what was going on, they took the fees off and applied my payment to the correct account.

My husband had an issue with a vendor who did not refund...