The Panasonic Zoom 100-300 for Micro-FT is a real surprise and indeed very positive. Despite the large front lens diameter of 67mm, it is amazingly light and compact in the 100mm position. It completes the focal range upwards in incredible 600mm KB-equivalent. One more reason to say goodbye to the larger and heavier conventional SLR. The lens is made of plastic but has a metal bayonet. The haptic impression is dibasic. Zoom ring and focus ring run quietly and softly. The focus ring (front) could be wider for my tastes, but is sufficient. OIS and focus are practically inaudible even in quiet environments. The Bokeh is especially nice and pleasant. Subjectively, the quality of the image quality is top notch. Sharpness and contrast are impeccable. In the upper range of focal lengths the lens slightly softer features (like all zoom in this area), but this is minimal. The vignetting is subjective (readings I have not seen) negligible. The image stabilizer is reliable and very effective, but can the limits of physics course not overcome. A Statv or a slightly faster shutter speed is useful as with all longer focal lengths but not always necessary. Total earned 5 star at a reasonable price for the quality and performance. No alternative for owners of Lumix G-Systems in Puncto optical performance and weight / size. Who the price seems too high should not forget that is makes also use, due to the low weight / size, this lens much more common because it fits easily into the small bag Photo.