Any bag can be used as long as have kind of same dimensions of the ones provided and dont interfere sensors

You can use any rubbish bags that will fit. I use 60 litre bin liners. They are a bit big but 20 litres, for example, are too small because the waste compartment measures approx. 50/50 cm.
The sensor then simply shows me 20-25% full when I have changed them. But it doesn't bother me.