Ok, thanks for all your replies.
In my experience, stuff breaks, be it from faulty parts, general use, someone kicking it(on accident or on purpose), circuit board shorts out, etc.
I wanted to know what my chances of recovering the data on the drives was if the actual NAS unit stopped working for some reason.
What got me started thinking about it was a friend of mine has raid 0 on his motherboard, so he basically had a mirror of his system, and I asked him what happens if the motherboard dies? He didn't have a good answer, and it got me thinking about NAS Units that people use for media storage, what if the NAS dies but the disks are ok, can you move them to a different NAS and they will work, and if so, how? Is it easy or hard to do?
So it is good to know that you can do that with some units depending on how they are set up, and that will help me make a purchasing decision in the future.