This i4 Roomba is good at cleaning up the pet hair and it is consistent, once the map was learned. Yes, the clean out function at the end of each run is loud, like other reviews have said, but the tower unit does suck out all the junk from the robot's bin. My issue is that I ordered this on July 9, it worked fine for about a month of four times a week cleaning, and then I paused it while we went on vacation, and by the first week of September, it was giving error code 2, clean the brushes. I dutifully cleaned the hair from the roller brush ends and removed the plastic roller caps and cleaned the hair spooled around the roller shaft, but discovered that the lighter green roller was not spinning at all because the metal axle had completely broken (it's supposed to be sticking up out of the green roller, but it's missing in the picture I've attached below). I called amazon support, was put on hold for 35 minutes, and then my call was "disconnected" after speaking with somebody about this problem. I called iRobot and they said their offices were closed (it was Labor Day weekend). I decided to order a new pair of roller brushes (the real iRobot parts are RIDICULOUSLY expensive, but I wanted to make sure I was using authentic parts), and that solved the problem! But it should've been covered under the warranty, and I should'nt have had to pay all that money for new roller brushes. I called iRobot support again a week later, and after 15 minutes of holding, a customer service rep took my information, and said they would ship me an entire new brush head module, since it was only two months since purchase. Then he put me on hold for a further seven mintues to "check with a manager," and again, I was disconnected from the call. At least this time they did call me back, and told me that they would send out the new brush head module and it would arrive in seven to ten business days. We'll see. I'm concerned that I'm doomed to keep ordering roller brushes. All told, it was almost $30 in the hole for new brushes and almost an hour on hold on the phone. Super hassle. If you have similar problems, don't waste your time like I did and call amazon--go directly to iRobot support. I'll update this post if I actually get the rollers in the time frame promised.