hmmm - I use Shiseido's salicylic acid gel when I get a cystic breakout…it works almost too well, because rather than just soothing the swelling under the skin, it wants to dry up every drop of sebum and infected matter in there, sometimes causing the blemish to hurt more and stick around longer as it brings it all to the surface like a tractor beam. It totally clears it out, though, rather than just masking the eruption or just drying the outer layer. The only problem with the Shiseido one is it's in a squeeze bottle that always squeezes out twice as much as I need for just one zit and this is a product you do not want to over-apply, so I wind up wasting some of it. Seems like the MAC one might have a little better applicator for more controlled application, plus it's the same price as Shiseido. If it comes out, I might get a tube of it when I run out of my bottle of Shiseido.'