I apologize if this question is asked already or asked often, but the search terms were too generic to yield any helpful, existing threads on this topic.
I just wanted to know if there were any risks or disadvantages to upgrading my 211j to the latest version from an older version. I am aware of several advantages/features that will come with 4.0. My main concern is that I do not want to lose the data currently stored on my NAS.
Basically:
Will my data remain intact?
Will my current configuration and settings remain intact?
Will my admittedly older, less powerful unit have any performance issues after upgrading?
Thank you in advance for your help.



