Gigabyte X58A-UD3R (FH) max RAM ?

I currently have 4x4GB RAM installed. I know the max is theoretically 6x4GB, but I've seen lots of reports online of people successfully installing more.

1. Has anyone had success with 6x8GB?
2. What about 4x4GB + 2x8GB?
3. What about 3x4GB + 3x8GB?

Thanks!