Great lens for the price. The optics seem better than the Olympus 40-150, although you pay a weight penalty and some extra cost. I use this lens on an Olympus EM-5 and overall am very happy with it as a modest upgrade over the Olympus lens. Neither lens is bright enough, but that comes at an even higher price in terms of weight and cost. . If you prefer a lighter lens, the Olympus 40-150 is still good, and the quality improvement from the Panasonic is modest. I'm willing to accept a slightly heavier lens just to add some sharpness.
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