Quote Originally Posted by Cowboy622
... when our power goes out in a severe storm, it is seldom out for more than 2 hours, ...
The fact that electricity is out for that long may indicate power quality provided in that area is susceptible to fluctations.
So Midknyte's second comments would definitely assist in keeping your system alive.

As for runtime of the UPS, may differ depending on total devices attached and running off the UPS.