I am quite picky about eyeliner and always looking for something that won’t smudge. I have oily, hooded eyelids, so that’s no easy feat.
I actually had the same meh experience as Renee with Stila Stay All Day Waterproof Liquid Eye Liner (funnily enough, I also tried the Cobalt).
For ultimate staying power, liquid eyeliners work best. Most recently, I’ve been impressed with two eyeliner pens by Blinc: the Liquid Eyeliner Pen and the Ultrathin Liquid Eyeliner Pen. I think both use the same formula: deep jet black, dries slightly shiny, comes off in flakes with water and gentle pressure or regular eye makeup remover, and–yes!–smudgeproof.