What is the main difference between the Roomba j7+ and i3+?

Regarding the Roomba: The j7+ uses a camera and PrecisionVision to see and avoid obstacles like pet poop, cords, and shoes, while the i3+ navigates by bumping into things. The j-series sees obstacles; the i-series feels them. If you have pets, kids, or leave things on the floor, the j-series is worth the upgrade for true autonomy.