iRobot 4150 Roomba Robotic Cleaner

This model Roomba is great! I've had a roomba red for 2 years and ordered this as a 2nd...We run 1 on each floor. The best features of the 4150 are the APS extended battery and Max mode. This has all the features I need.... Invisible wall and 3 cleaning modes. With 4 cats, 2 dogs and hardwood floors throughout the house, we run the Roomba regularly. It does a great job of keeping the house tidy. The only negatives; You need to pick up small area rugs and lift all lamp cords off the floor (these can trip up Roomba and get it stuck). The dust cup is a bit smaller than I'd like..be sure to empty the dirt cup and pre-filter area immediately after every cycle.