Depends on what you mean by "data".
If you have an autobackup, you have a backup of all configuration. A flash will only replace the root filesystem, it will not touch others, like on disks or sticks...
Note that if you have installed any packages manually (outside of the plugin feed), you need to install those again, manually. Everything from the feeds will be reinstalled after a restore of the autobackup.
okay i've forgot to ask about the oscam configurations from my provider. That was the main meaning of my question!
But if I've understand it by the right way those also wont be touched, right?