I had an interesting experience with these devices. I purchased one a week or two ago and noticed that Best Buy had it marked down to $145! I paid $200. So, I ran out and got a price match on the first one and bought a second. The second is for our theater room.
So I brought it home, hooked up the battery, and took it downstairs to the theater. I found a nice spot for it and got it setup. Everything condenses at the power source to three extension cords so I figured I would just plug them all in to the unit. That includes receiver, projector, subwoofer, dvd, cd, computer, 3 gaming systems, lights, vcr, video box, and other minor objects. I made sure the laser printer was hooked directly to the wall.
So I plugged it in and it started beeping and showing F01. That means on-battery overload. Hmm, it's plugged into the wall so it shouldn't need to use the battery. Plus, other than initial spikes, the power draw is well under 50 watts and this is capable of 865 watts.
So I unplugged it and I think I removed 2 of the extension cords. Then I plugged it in again. Then it blew a fuse! Well great. I then tried it in another outlet and it basically appears to be destroyed or something because it doesn't do anything worthwhile.
They shipped me a replacement overnight and it's working great now. At 300 watts power draw, it estimates around 15 minutes of uptime but APC claims 26 minutes at 300 watts. What causes this difference?
I've had the theater on battery backup for quite a while but there was a period where I stole the UPS devices for other equipment...what a surprise, in that time, I was in it when we had the power outage from the big ice storm. And someone accidentally flipped the breaker another time. I knew that couldn't be good for all the equipment.
$145 is a great price and Best Buy has 12% off coupons so I could get another for ~$135 (tax). It is a difficult expense, though, knowing we don't have outages too often. One was required for the server or it could corrupt the entire RAID 5 array...and the theater is reasonable. The other UPS devices I have were really cheap on sale. The only other two potential areas are my computer setup or our family room setup.
I still keep thinking about how I am so close to having just about every device battery backed up. It seems like a complete house battery backup system wouldn't be out of reach--perhaps ignoring the huge devices. How many watts do refrigerators, air conditioners, washers/dryers draw?