So, this *is* MAC Ruby Woo, period. I have both, and the only discernible difference is that Ruby Woo is more drying while Perfect Red is comfortable. It stays on perfectly well though talking and drinking, and fades evenly/gracefully after eating. It leaves a nice stain after fading. It's a bit creamier than, say, WNW Megalasts, but stiffer than normal/non-matte lipsticks. It went bad a bit quickly on me, at about 9 months, but I didn't mind considering the price. When it went bad, it smelled of crayons and no longer applied matte.