Judging external HD reliability

[dougsweetser-Re5JQEeQqe8AvxtiuMwx3w at public.gmane.org (Doug)]

Hello:

What I care about most is having a hard disk last 5 years under quite
modest use at home for standard definition video projects.  If I am
not going for the lowest price, do folks think the "enterprise"
distinction is worth the extra dollars?  Does it up the odds of the
device working over long periods of time?

What do people think about going with a gigabit NAS server for the home?

I have about 500G of videos I may watch a few times at most, and video
projects that took a few years to use up 500G of space for Final Cut
Pro projects.  I would like the iPhoto album to be centrally stored.

Doug