How long does the Roomba j7+ last and what makes it convenient?

The [Roomba j](https://www.amazon.com/s?k=Roomba+j&tag=wehavethat-20)7+ lasts 75 minutes — enough for most homes, but big layouts need the auto-empty dock for mid-job recharging. Voice commands with Alexa and Google Home mean you don’t need to find your phone to start a cleaning. That convenience is the real sell.