Everything works just great. This includes the card reader as well as the volume keys (which are extra added keys on the upper side of the keyboard) and everything else.
It's just great to have a Dell Latitude E5500 together with Linux Mint.
Sometimes the resolution is reseted to 800x600. But after you changed it again in the "screen-program" it is working again.
Worked out of the box. Install and be happy. :)