I love this lens and I am happy to share with you why. I am a professional photographer that has been publishing calendars of my own photos for 15 years so I demand good quality. You can see my work at www.apollopub.com if you like so you can see that I know a lot about photography and the importance of quality equipment. I switched to micro 4/3 about 5 years ago and love the format because it is much lighter and the lenses that are available are awesome. I have been using the Leica Lumix 14-150mm lens for years because it is a very good lens which has very high review ratings. I just bought the Panasonic 12-100 PRO lens and have been comparing it to my Leica lens and find it to be superior in many ways. First of all it focuses much faster. Secondly, what surprised me is that the colors were more vivid and the shadows weren't as dark. (It made it look like my Leica had sunglasses on compared to the Olympus). Thirdly, the image stabilization is far superior. Fourthly, it zooms very smoothly and the lens doesn't creep like the Leica did. And for me there was the added bonus that it was from 12mm (24mm equivalent) which helps a lot for my landscape photography.