I have hormonal acne that I keep under control using some Retin-A, zinc, avoiding dairy, and taking a hormonal balance supplement. But every once in a while, I still get blemishes. This stuff is great for occasional pimples. The only drawback is that it seems to lose effectiveness about half way through the bottle. Like a lot of acne medication, you skin seems to adapt to it. But if I wait a few weeks and try it again, it works well. Effectiveness The sulfur in this product is really good for skin. This is effective on most pimples (although it won't do much for deep cystic zits, I use arnica oil for those), and dries them up for me within a day or two. Ease of Application This is one area where this product lacks. I just use a q-tip to dip into the separated pink part and apply. I tend to run out of the clear liquid faster than the pink part. Convenience I have bought this at the drug store, so it's not something you have to buy online and wait for shipping, which is great when you suddenly have a zit ;) Side Effects I have experienced minimal side effects from this, some slight drying. But it's really not that bad, and only happens if you use it over and over in the same place. Immediacy This takes away or greatly reduces the size of pimples within a few days.