I have grown to try to minimize battery backup. Maintaining and changing batteries is such a pain. The other good thing about a generator is that it can replace many backup batteries and will run as long as you have fuel. Our in ground propane tank will be a 500 gallon unit (400 gallon capacity with the required expansion head space) which will give us a lot of run time. I certainly have UPS backup for critical applications where a second or two downtime is a problem and to allow for the generator to start and stabilize before the transfer switch cuts in. But for things like the sump pump and the grinder pump whose electrical requirements are much higher than the sump pump, the generator is a better solution.