We've done it before and it's a little nerve wracking but it works. When we did it it was pretty fast, but the emails indicated it could take more time. When we submitted the request we got a note saying it might take 3-4 weeks to process (but it was processed the same day.) Then when it was processed we got another email saying our cc would be refunded in 3-5 days. I don't know how long that actually took.