I have three of these things. They're all neutral using devices, not the battery operated sort. One is an intermatic, the others are whatever was in whatever big box hardware store I was at had, so one HD house brand, the other probably from Menards. They all work fine, and have for years. The accuracy of the clocks isn't terribly great, considering they're running off line current; the intermatic is about 9 years old and is about 20 minutes fast. The other two are newer, and are closer to right, but still fast. This doesn't bother me, they control the porch light and outlets for holiday lights. They're all dusk-to-dawn, +/- some small random amount. I do need to fix the intermatic, because my wife complained the light was off when she left for work recently. But I haven't, because programming these things *****. crazy interface, tiny screen, tiny buttons. They're all different, of course. But they're pretty much set and forget, devices, so if the clocks were better, that would be fine.
No problems with power outages, but the longest we've had has only been a few hours. they're all supposed to have a rechargeable battery to keep them set over an outage, and it should last a long time.