|after about two weeks and various attempts I cannot recommend this brush.
at first I tried it ungrounded for a couple of days and noticed no difference between it and the Hunt EDA I normally use. the mat actually came up with the record.
then I grounded it with the preferred instructed method the cord to the screw holding your plug cover to the wall. no change still ineffective. then I tried an alternate grounding to my power conditioner ground screw. no change then to my phono pre amp ground screw, again no change.
exasperated I then tried various speeds and number of revolutions of the disc sweeping and from fast to slow exiting the disc. again no luck.
while it does an adequate job of removing dust, no more or less than the Hunt brush, it is not an improvement... I used it in low humidity 35-40 % , on both a thin leather mat and a thin cork mat. the mat material made no difference.
not at all what I expected from a Stereophile recommended component