I would recommend getting something that uses a true sine wave output vs the less expensive stepped sine wave. I use an APC Smart-UPS on my SO3, and here is a video from a few years ago where I had it running and just pulled the plug on the UPS, and the SO3 didn’t even notice. I was in the middle of changing out the router, so it is just sitting on the deck, but it is a good demonstration none-the-less.