[Product Question] Paula's Choice marketing isn't making sense to me. Could someone explain?

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I see the PC C15 recommended a lot here when I was searching for a new antioxidant serum and I'm a bit confused as to why.Resist C15 Super Booster: http://www.paulaschoice.com/shop/skin-care-categories/antioxidants/_/Resist-C15-Super-BoosterResist Ultra-Light Super Antioxidant Concentrate Serum http://www.paulaschoice.com/shop/skin-care-categories/antioxidants/_/Resist-Ultra-Light-Super-Antioxidant-Concentrate-SerumThe second antioxidant I linked is what I have my eye on because it not only contains Vitamin C, but also niacinamide, resveratrol, hyaluronic acid, etc. The thing the C15 has that the other doesn't is ferulic acid. Isn't the second serum I linked better? I learned from lurking here that niacinamide helps lighten skin. Yet the product page doesn't mention that at all. It does mention that on the C15 product page which is primarily Vitamin C focused, something the other antioxidant has too.
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Submitted by glowinthedarkskin