Lovesick is amazing. I get compliments all the time! And I find that they make your lips look very plump (who will bother to look at your teeth anymore?). I used to have more yellowy teeth before (I couldn't wear bright reds because it would look bad) I whitened and it didn't show with lovesick on.
If your teeth are less white, I would DEFINITELY try some of the more violety/purply looking shades. Colors with a blue undertone are really great for making your teeth look whiter. I would recommend Sweetheart, Darling, or Cherish.