Hi, I am looking for a logical wide-to-standard prime choice to my Pan 12-35mm zoom lens. Currently it's my only lens for my Oly OM-D E-M5. I love the idea of the 20mm 1.7 pancake, especially for the size, although most suggest the 25mm 1.4. I've been watching/reading reviews of the 12mm f2 as well. What do you guys suggest? Thanks J.