I would like to buy a prime around 20mm. Obvious choices are the 20/1.7, the sigma 19/2.8 and the 25/1.4. the 25mm is too expensive, so the 20mm (used) is an option (€ 200) and a new Sigma 19/2.8 (€99). To me, I would favour the 19/2.8 because I would save some money for some accessories/software/filters. Current set-up: Camera's: OM-D + Pana G1 Lenses: Pana 14-45 + 45/1.8 + Vivitar (Komine) Close Focus 28/2.8 + Pentax SMC 50/1.7 + Takumar 55/2 Size is not the most important reason for having the preference on the 20/1.7, but the larger aperture is because of the ability to shoot with narrower DOF. I browsed through the image thread of the 19mm, but couldn't find a lot of shots having a small DOF. I would like to see some examples with narrow DOF with this lens to see if this is possible... How is the speed of AF with the 19mm in comparison with the 20/1.7 ?