Haven't checked if noatime is added to fstab for sda stuff when running from CD, but it should be IMO.
Without it the access time is written to the stick every time you/knoppix read a file from it which will shorten it's lifetime. Perhaps not significantly so, but unnecessarily.
My line is: /dev/sda1 /mnt/sda1 vfat noauto,users,exec,noatime,umask=000,uid=markus,gid =markus 0 0
You could probably get by with: /dev/sda1 /mnt/sda1 vfat defaults,noatime 0 0