After the BB shilling, I tried some of these the last time I moved out of a apartment and needed to do a thorough cleaning. Not particularly impressed; they fall apart orders of magnitude quicker than green scrub pads, and I don’t see any advantage in effectiveness except perhaps less rinsing as the disintegration of the magic eraser constantly exposes new surface.
Mark’s use case of removing sticky goo is probably the best use for these as rinsing sticky goo out of green scrubbers is painful. But for ordinary marks and stains I will stick with green scrubbers.