seek backup generator advice

Anyone have experience with backup generators? Frankly, this issue pertains to my place in rural upstate NY, not my place in Bklyn.
I’m considering a Guardian standby generator vs. a battery operated emergency power system made by Altapower. This is to power sump pumps and furnace in the event of a power outage. Probably not a Brownstone relevant question but maybe some brownstoner has a rural domicile and has considered this kind of technology.