32 GB card has been used, I'm not aware of a bigger one available today.
http://www.benzworld.org/forums/w221-s-class/1276007-pcmcia-card-adaptor-4.html
http://www.benzworld.org/forums/w221-s-class/1276007-pcmcia-card-adaptor-4.html
According to the manual (you can read the Euro manual on-line if you want to get familiar with a car before the delivery) MB supports 255 folders per disk. Each folder may have 255 sub-folders, at maximum 8 levels. The total number of titles per disk is limited to 4000 (there can be more but the system only reads the 8 first folder levels and the first 4000 titles).Yeah, I also think this is the largest it gets. But the question is whether or not the S class computer would be able to read all the songs if they are like 4000. Because in the past I had BMW E90 320i, and the iDrive could play mp3s from a DVD, but it would only play the first 250 songs on the CD, and the others do not appear anywhere.