OK, I see. Over here in Holland we only have about 2 or 3 outages a year, and the voltages are quite stable. So far I never had any problems with my PC. But I agree, it makes sense to protect it, you never know what might happen in the future.
@Bill_Bright thanks for clarification. I pretty much agree with everything you said. When I researched this many years ago, (and it was every bit as involved as researching what computer would fit my needs at the time) I remember reading transients and other anomalies can be generated by the devices themselves, which ties in with what you said about it's not all the power grid. I keep my vacuum cleaner well away from my gear. I also wear an anti stat strap when I'm fiddling inside computer. I'm no trained techy but I try and do the right thing. Brown outs are absolutely the pits. When they've happened here it's mostly just a number of seconds but the voltage can vary as to how far it goes down. We've had a couple very low voltage episodes lasting for a long time ....ie light bulbs barely showing they're on. I shudder to think how our freezer and fridge would have coped had I not been home to switch them off completely. Also I'm pretty sure when the power comes back on there's a huge draw on the power as everyones electrical devices get turned on again. For that reason, plus waiting for the power to "stabilize" I wait for some minutes before I turn stuff back on. When you're rural you learn to do these things.