My lawn approx. 400m² turned into a foam mat and the usual treatments were not enough at all. Scarifier becoming necessary, I chose the AL-KO Combi Care first for its quality / price ratio! After a quick installation, I first tried the roller blades: the ferry was already full after only 20m, and level 2 only: so I removed the tray (knowing I would have to pick up after). I spent the scarifier again at 3 and same result: a moss fields and various plant waste to be collected. I then immediately handed the tray and made heaps around the garden (easy to pick). OK result. Two weeks later (time to see how it evolved), I tested the claws pin on an area that was still a little damage: still lots of foam sprinkled in the garden! Since then, over problems with the foam. I wait for the grass regrowth everywhere and we can soon enjoy again a lawn in good condition.
I think we can use this machine regularly (at least 2 times per year). It is very comfortable, light and easy to handle. I think the level 5 transforms this scarifier cultivator (blades down very deep). Side "defects", the tray could have been bigger and the Aerator does not hold standing.
Finally, do not wait. Order it and a few days later you'll have enough to clean your lawn effectively.