I own the Xiaomi Roborock 2 and the brush was for this model. Unfortunately, I don't know if it also fits other models.

Unfortunately, I can't answer that. I don't know the product that is being asked about.

Yes, I have used them for our S5. Works fine, only downside the wheels on the other side are not removable to remove the hair, so you have to cut.

Yes, it is compatible and I have tested it on my Roborock S6.

It is of course understandable that you would not agree with the price if you could find this brush cheaper elsewhere. Unfortunately, we effectively already receive this brush at a higher price from our supplier, as we have to import it and cannot source it locally. If this changes, we will of course adjust the price.