In summary: only use this app if you're willing to gamble that you will eventually get the rewards! There is no phone support, and I am not convinced that their email support is competent!

After installing this add-on, it recommended I purchase something from a different site than Amazon.com so I can save more money after cash back. I made sure the offer was activated before my purchase - the add-on indicated it was. Two months after my purchase, I still haven't received the cash back.

There is no phone support for CapitalOne Shopping - you can only email them. Regular CapitalOne credit card support will not help you with CapitalOne Shopping issues.

I emailed them about my purchase on Chewy.com and they responded that they did not see any record of a Macys.com purchase (!?). I emailed back that it was through Chewy.com and they said they still found no trace of it. I asked if they could give me credit given I have a receipt and I used the card and followed all instructions, but they have not done so. I'm afraid that I will never get my rewards...

The coupon codes also usually don't work at all.