Summary: This lens is so very impressive!!! It's bigger money to pay out on a lens, but the results in the photo is worth it. I shoot with an Olympus E-5 and also the omd-Em-5. the lens works well with either camera. Although with the M-5 it looks hilarious. It is very heavy to carry around hiking. I've gone to a belt system to accommodate the weight difference.
Summary: I have over 40 year experience in photography. .Used the leica camera in the 70s..olympus in the 80s..Minolta in the 90s and I presently shoot wuth the supreme olympus e5 and nikon d800e and d7100. I love my fx d800e nikon especially paired the the stellar 70 to 200 vr2....yes pictures comes out absolutely beautiful with some fine tuning in photoshop. Olympus e5 with the zuiko 35 to 100 pictures come out lifelike with no post processing 95% of the time...
Summary: AT least for me. The focusing is not as sharp as it 'should be' for the price, it is incredibly cumbersome, which I would happily deal with if I got the performance out of it that I was promised. RETURNED it to buy (H & B).....not B&H and was told since there was a hairline scratch on the outside (there was not, at least not when I sent it back) it could not be returned. Also H & B said that I did not return warranty card.
Summary: I use this primarily with my E-5 and it's easily one of Olympus' best 4/3 lenses. Can shoot wide open and works amazingly well for indoor sports like basketball and hockey. Portrait shots are a dream as well. Focus isn't blazing fast but the limiter helps and it rarely misses in quick shooting conditions. Sealing holds up great. I've used it to shoot a number of Spartan Races and it shrugs off water and mud without a problem.
Summary: I've had this lens since 2009 so here is the real life usage summary. 1. Extremely bright lens - f/2.0 and fastest(aperture) in its class. I've found this to help me overcome 99% of all lighting obstacles in a zoom. 2. Focusing speed is better than average - I have to be careful here because this depends on also your lens and what aperture you are shooting. The camera body and focus point choices in the body are big factors.
Summary: This is an incredible piece of photographic equipment. F 2.0 through out the range, sharp and clear beyond anything I have ever seen. Had to save up for a long time to get it but worth every penny for sure.
Excerpt: Just getting started with using it. Other than being pretty heavy when it and the camera body are supported by the strap around your neck, it could very well be my primary, all around lens. It is fast and being able to use the full telephoto and still have a decent depth of field is great. Sharpness thus far has been very good.