The Olympus is great for parades and outdoor portraits, but you not so great for candid shots because you have to stand so far away. The Sigma is easier to work with in that regard. Otherwise, I think the output is pretty similar.These images are fantastic, the rendering this lens produces looks great!
Im a few months out from picking one up, but for those who have handled both do you prefer the Sigma 56mm or the Oly 75mm F1.8? I can get the Sigma new for about the same price as the Oly used with some hunting.