I bought my parents a Roomba E5 (e5154) for Christmas, and the rollers failed after only ~2 months despite regular maintenance and relatively clean floors. Sadly iRobot refused to replace them :/
Roomba e5154 iRobot Støvsuger
Irobot Roomba E5154 Robotstøvsuger - Kaataq EL
Roomba E5154 iRobot: programmable and autonomous Vacuum Cleaner
Roomba e5154 - REF A
iRobot Roomba E5 Robot Vacuum E5154 App Silver - Dealer for sale online | eBay
Irobot Roomba E5154 Robotstøvsuger - Kaataq EL
NATNO 14.4V 3200mAh Battery for iRobot Roomba i3 3150, i4 4150, i7 i7+ 7150 7550 i7158 i7550 i7558, e5 5150 e5150 e5152 e5154 e5158, e6 6198 e619820, Roomba e and i Series 4624864 ABL-D1 - Walmart.com
iRobot Roomba e5 e5154 - Smart homes - smartphone control
iRobot Roomba e5 Wi-Fi robotstøvsuger E5154
Home cleaning made easy with iRobot's new Roomba e5