At first glance, you would notice that the base station of the Dreamebot L10s Ultra is bigger than that of the Roomba Combo J7+. This is not surprising, considering that the base station of the Dreamebot has 2 water tanks and performs functions that Roomba Clean Base. At first glance, you would notice that the base station of the Dreamebot L10s Ultra is bigger than that of the Roomba Combo J7+. This is not surprising, considering that the base station of the Dreamebot has 2 water tanks and performs functions that Roomba Clean Base.