Disputing a credit card transaction?

Has anyone ever disputed a credit card transaction?

What credit card company was it with? What was the situation? What information did they require? How long did the process take? Outcome?

I had an extremely poor experience a little while ago, both in terms of products AND service. I've attempted to handle the dispute directly with the merchant (and have forms/documents to prove it) and nothing has come of it, so I thought I would try the credit card company. This is a fairly large sum of money, and I don't think I should be responsible for paying for something that ultimately turned into a nightmare.

I paid for a service. It never happened. I called Mastercard, they had no issue going after the merchant and a refund was on my next bill.

Same as above. I was charged for a service I didn't receive.

I paid for some handymen to come to my apartment and set up some furniture.. they rescheduled twice, were 3 hours late, then said they had to reschedule AGAIN because they needed more tools. This is IKEA furniture mind you..wtf kind of tools do you need?

End of the day I made my brother do it. But my credit card was STILL CHARGED.

Wasn't in the mood to deal with the handymen..went straight to American Express. Gave them the handymen info etc...Money was back within a month.

It should be pretty easy. They send the merchant a letter with a deadline to answer (which is basically ignored as the card companies have the upper hand) and then withdraw the amount out of the merchant's account at the end of the deadline.

It works well when the customer's right