In the bottle, Mojito Madness and Starboard look eerily similar, but Pretty Edgy is already visibly darker. On the nail however, Starboard and Mojito Madness look very different. In fact, Pretty Edgy and Starboard wound up being much closer to each other than either was to Mojito Madness!
L to R: Essie Mojito Madness, China Glaze Starboard, Essie Pretty Edgy, Essie Mojito Madness
Formula-wise, I'd say China Glaze was the best, although they're all comprable. This was two coats of each polish. If you already have either Starboard or Pretty Edgy, you're safe getting Mojito Madness. It's easily the brightest of the trio and a very different type of green than the other two.