When Parts Geek sent the wrong part. I had to pay the postage both ways, then a 15% restocking fee for their mistake. So my net refund on a $37.98 wrong part was about $7, and they get to sell the part again.
So it's actually profitable for them to send wrong parts. The one I got came in a scuffed and obviously pre-opened box, so they may have "sold" it several times, collecting 15% each time.
When I called customer service, the first operator disconnected me right after I said hello. Then, after waiting on hold again for a long time, the second operator referred to the wrong part on the invoice and blandly insisted that I ordered a part for a car I don't own.
This company is, by far, the worst online business I have ever dealt with. Forget the good reviews--if they make a mistake (and from the fine print and their return policies, they must make a lot of mistakes), you will lose most of your money as I did.
There are many good auto parts companies on the web--avoid this one