I picked one up a few months ago and count not be happier. Obvious sonic improvement - even on clean, brand new records.I don’t have a Degritter - I use a Klaudio US machine - but your experience doesn’t surprise me at all. LPs aren’t pressed in clean rooms, so even new ones have some dust or other contaminants on them. And there is dust in even the cleanest homes; if you need proof, just observe any sunbeam streaming through a window. Dry brushes can remove only the most obvious dust. And the "sweep arm" type brushes actually grind some of the dust into the LP surface. They should only be used on LPs that have been properly cleaned first, if at all. I find them useless. They can be a Band Aid for static problems, but I don’t think they’re the best solution even for that.
Visible dust on your stylus is proof that your records aren’t clean. It’s amazed me for years that many audiophiles have never heard a truly clean record.