This is for a certified refurbished model, which is why it is so much cheaper. Seeing as the i7+ is typically closer to $799 normally. The Roomba i7 has some pretty powerful suction, enough to deliver 10x the air power for better pickup performance compared to the Roomba 600 series. This means that it is unlikely to leave any dirt, dust, or hair around your home, once it has finished cleaning. It will also intelligently map and remember multiple floor plans. So that it is able to clean your entire home. It includes the patented iAdapt 3.0 technology with vSLAM navigation. So it is able to accurately map out your home. This allows the Roomba i7 to accurately clean your home without missing any spots. This one is also ideal for those with pets. Since the high-efficiency filter will trap around 99% of cat and dog allergens. So if you are allergic to dogs or cats, this is the robot vacuum to pick up.
