Had some on the gravel bike. Poor. To the point where despite 2 bleeds, clean everything , proper bedding in – the front wheel could be pushed round with brake full on.
LBS went ‘these are bobbins’ popped some Shimano resin ones in and problem stopped. brakes all good.
In the interests of balance ran some on the rear and they stopped – but did not inspire confidence.
Used Superstar and Uberbike without issue and been running disc brakes (on various kit) from 1999.
Mebbe I had some duff ones, but I won’t be going there again.