Swatches dry on skin, indoors, zero flash to give you a good idea of what it'll look like on. Both are very fine milled, apply cloud soft, and blend with a bronzer brush (EcoTools bamboo bronzer is a perfect match with this sort of powder). The key difference is that MAC is a bit more pink and has silver glitter.
Above is a heavier more concentrated swatch. Below is more buffed out. The MAC powder does 'stick' more, but I don't care for that when I want a fine, dewy glow. But if I want a highlight, then yes, more oomph is needed. What do you prefer? Would you want the MAC so far, or the Coty? Don't be swayed by brand here, no one is more impressed with your fab skin just because it has a MAC price tag.