I can't recommend against the APC UPS units strongly enough.
For a number of years, they were the solution we used, both at office, at the disaster recovery site, and at home. The most time consuming issue was that after the initial battery failure (at approximately the 2 year mark), subsequent replacement batteries would work for about 6 months to a year, and then require replacement again too.
But that wasn't even close to the worst issue. Even though I would test them regularly, what would happen of course is that when power would fail, they'd be dead and I'd be dealing with data corruption. And what was even more frustrating is that more than once, I had different units that tested fine fail to "kick in" fast enough in a power outage and the systems they were supposed to be protecting would reboot.
If you're going to bother with a UPS in the first place, use a dual conversion battery backup that's actually worth spending the money on - something like this:
http://www.tripplite.com/en/products/model.cfm?txtSeriesID=744&txtModelID=3194It's not a UPS in the "traditional, take over when the power fails" sense. Instead of trying to switch to battery when line power fails, a dual conversion system is constantly converting line voltage to DC, maintaining the battery, and running the inverter to generate clean conditioned power for your computer equipment. It's like having your own mini power plant constantly generating the electricity for your computers, so regardless of how ugly the power coming in is, the power coming out to your computer is stable, clean, and consistent. Oh, and best of all, since all the components are in use all the time, there's no
!!!SURPRISE!! when the line power fails.
With the APC's, life was hell. With the Tripplite's, I've not had a single issue.
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