For me it replaces the normal hoover, I still need a hand hoover.

Well, I can only agree with the previous speakers. The new navigation system of the 900 series is really strong! The Roomba really reaches every place on the floor that it can reach due to its size. It efficiently covers surfaces only once, followed by wall and corner mode. Objects in the areas are also targeted and briefly circled. When it has finished, it also returns to the charging station in a targeted manner. It does not close doors (in 75% of cases it slows down in front of an obstacle).
However, it should be noted that furniture with a floor clearance of 8.5 to 9 cm is a potential trap as it can wedge itself underneath. Flat/sloping furniture legs with a ledge at the edge of less than 1-1.5cm the Roomba wants to climb or can get trapped on the other side. Both are the case with me, but I have to say that up to now it has always been able to free itself extremely quickly.
My girlfriend's long hair is also no problem with the rollers. Even notepads on the floor are picked up. It is almost disgusting what dust it picks up in a 2/3 day rhythm!
I can't say anything about cables, but there are no cables lying around on the floor. In two places there are cables running along the wall in a cable hose, but this is no problem for the Roomba.
Well, yes, it replaces the hoover, but we also use it in combination with a hand vacuum for spider webs, radiators, furniture, car, etc. and for cleaning the Roomba itself. As it divides the flat into virtual quadrangles, its action is sometimes not logical or jumps from room to room, but never misses a spot! However, as already mentioned, this is fascinating to watch how purposefully it moves around the flat :D

The Roomba will change your life (no matter which model) and replaces a normal hoover on the floor as it is much more thorough and independent (you will be amazed what ends up in the collection bin). However, it can't go up walls and ceilings so a normal hoover should always be handy for cobwebs, radiators, furniture, toys etc. . And you have to remember that the dirt does not end up in a bag but in a container that has to be cleaned by yourself. And if you decide to buy one, make sure you don't catch yourself watching it at work or the time you've gained will be wasted;-).