In my experience, the bigger issue with Verizon's battery backups was that when the battery starts failing, the device beeps loudly every minute. That's especially problematic in apartments, as it tends to be within earshot of the bedroom. And the battery backup system is present in the ONT box even if you don't have phone service, or ever want it; and even if you own your home, it takes a lot of complaining to get Verizon to remove it. Horrendously stupid design.