Having lived under the thumb of Comed here for many years. I went old school. Simply because batteries die. And Murphy will determine when they die. Usually right before the power goes out.
The mag light is in the charger by the door to the garage. Easy to find and grab. That allows me to find: the 4 hurricane lanterns (like this
https://www.vermontlanterns.com/content/large-wall-lamp-brass-125 only with the hook thingy to put your finger through to carry it.) for something like $5.00 many moons ago when the local Ace had them on clearance. The quart jug of designer (green colored) lamp oil was $1.89 IIRC. I've only filled the lamps once and they are still ~half filled. They produce enough light so that you won't bang your shins on the coffee table and keep the women-folk from panicking. They do a fairly decent job of lighting a work area. (Enough to fiddle around with things that need fiddling around with to right the ship.)
I've got a breaker panel that isolates the two circuits that have the sump pumps (2 in holes and a backup plumbed and ready to drop in a hole, on the shelf) and fridges. Roll out the generator (5 gallons = 8+ hours) and Festung Scout is back in the fight. I keep 10 gallons on-hand in cans and the cars (at least mine) are never under 1/2 a tank or about 10 gallons.
Longest we've gone without power is just under 24 hours. Haven't lost food, haven't had more then some seepage in the basement. The only issue we have is that both ends of our street flood, but if we ever have to abandon ship we would merely have to walk out the back yard through the neighbors yards to higher ground and try to flag down a passing ark.
After I've got Festung Scout upright and afloat (a 20-30 minute process at most). I go check on my neighbors. From my experience and JMHO, those basement watchdog pumps are crap. Even if the battery works, the reason the power is out is generally due at a storm of type. And a storm means buttloads of water. And that little battery powered pump fails for the following reasons: 1) The battery is dead/hasn't been maintained/replaced. 2) If the stars are properly aligned and you just did maintaince/replaced it the day before the battery will die at ~7.5 hours. 3) The cheapie ($89) Ace Hardware Store 1/3 HP pump you installed pumps 2270GPH at 10'. The mid-level Basement Watchdog pumps 1730GPH at 10'....and recall the reason why the power is out in the first place. The key is to pump out the water at least as fast as it's coming in.
I've had two different neighbors install Basement Watchdog's and both times they failed. One because the water was coming into the sump at >1730GPH and it just couldn't keep up. It was heartbreaking to hear the pump run and still watch the water rise in his basement. The other was because the last time he had checked the battery was when it was installed 3~4 years prior. It died after two hours. They both lost the battle with the water. Fortunately, having water fill your basement through your sump is not a flood, most/some/a few HO insurance covers water back-up, yours probably won't....See Murphy above.