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Bought some Mirka Abranet sanding discs too, and the dust extraction is so good now it produces virtually no dust at all. The light around the sanding head also highlights every imperfection on the wall amazingly well.
It's a bit on the heavy side - almost 7 kg - but I can deal with that. Luckily I only need it occasionally.
Robota S22 is the exact model, in case anyone's interested. Paid 170€ for it. There were cheaper and lighter ones, but those didn't have lights.
Compared to doing it by hand? Well yeah, a lot faster. I do this for living so the cost is easier to justify but I don't think there's going back after you've tried one of these.