Primers vary depending on the type of silicone used (dimethicone being the most common). Dimethicone has proved to be used as a skin protectant, which is good to not only treat individual issues with your skin (acne, burns, etc) but protects your skin from bacteria, as well. Cyclomethicone is good because it's non comedogenic and outstanding for those with oily skin types. I think you can weigh the pros and cons and the strengths of dimethicone definitely outweigh the weaknesses. Overall, it is good for your skin.