I was curious to see how my legacy OM Zuiko 1.8/50 and 3.5/135 compared with the current 40-150 zoom. The Zuikos both have adapters to make it a 'fair' comparison: E-PL2    ---    33mm    f/5.0    1/20s    ISO 800 E-PL2    ---    22mm    f/5.0    1/25s    ISO 800 Obviously the legacy lenses are smaller than the zoom, when the zoom is extended. On the other hand they are a lot heavier and don't have auto-focus. Image quality is very similar in my opinion. Of course the 1.8/50 is significantly faster than the zoom, so I think it's worth carrying it with the rest of the kit.