Does Scotchbrite scratch aluminum blocks?

I am replacing Head gaskets on a Subaru 2.5 engine. There are a lot of posts about how critical it is to really clean the surface. This had a new head gasket not that long ago (Done by a dealer) and it was starting to leak again. (Too long for warranty but too soon to be leaking again).

Just remove all of the old gasket material, don't worry with a stain!!.. You ain't going to scratch the block with that or even a fine grit sand paper anyway!.. It just needs to be clean of foreign material...