I like this app because it doesn't try to be big. It's a small window, very cosy. The only thing I'm missing is a functionality where you can after colorpick get the links: to Dribbble search with picked color, to Coolors/Colorhunt palettes using picked color, etc.
I absolutely love ColorSlurp. The ease of access from the menu bar and the window that gives a great amount of information on the color is what makes me prefer this app to Sip.
I'm happy to say I've finally found a phenomenal, free, alternative!