Excerpt: I do a lot of backpacking, hiking, and candid portraits. I was hesitant to upgrade from my 15-85 due to weight and cost. However I took the plunge just before a vacation that included lots of opportunities for nature and portraits. I am extremely glad I made the investment. The scenic images are clear, crisp, and accurate. the portraits are beautiful. The benefits of the lens outweight the additional weight. Buy this lens!
Pros: Consistent Output, Fast / accurate auto-focus, Nice Bokeh
Excerpt: I love the ability to lock the lens. Since I do a lot of traveling this helps me feel assured that my equipment isn't sloshing around in my bag. The additional elements in the lens help obtain a clearer image.
Pros: Consistent Output, Durable, Easily Interchangeable, Fast / accurate auto-focus, Strong Construction
Summary: I suppose the IS is not needed in a wider lens due to the focal length, but I can see it being useful at 70mm.
Pros: Typical canon sharpness build quality and reliability. I have all canon glass and this purchase recently is one of the few lenses I didnt have to bridge the gap between the ultra wide and the super long stuff.
Excerpt: I have never been a huge fan of zooms, because honestly most of the time they just suck and have no real "love" in the lens. I used one of these that I borrowed from Canon and was blown away - razor sharp, edge to edge. Wonderful color and great contrast. I ordered mine from B&H and it was even better. As a working wedding photographer, finally having a zoom that isn't a pile of junk will alter how I work.
Pros: Consistent Output, Durable, Fast / accurate auto-focus, Nice Bokeh