I had to do a chargeback with EMedsDirect about a year ago. I was a little hesitant because I was worried the credit card company would ask questions. Then I decided that it was none of their business and I just pursued it through the proper channels, which, in this instance, was to write a letter to the cc company.

I got my money back. You really need to do it if it's warranted because it reflects badly, on the vendor, which it should, if they're stiffing you. This affects their ability to receive credit card payments, eventually, if they get too many chargebacks.

And, finally, you need justice. Being stiffed is bad for the soul. You need justice. Give 'em some consequences!

Good luck!