I bought this lens for a trip to Alaska. For the money ($500 at the time of purchase), it takes great pictures throughout it's range.In lower light, you'll need a tripod for clear shots while zoomed out towards 300mm - your hands just won't be steady enough. It also had occasional trouble focusing while zoomed all the way out but none while zoomed in just slightly from there.I thought it had good bokeh and no vignetting that I could discern although I'm no pro and I didn't compare against anything else. It also held up well during a relatively rough two-week trip during which it got rained on a bit and taken out on back-country day hikes - it never missed a beat.Overall, a great value for the money if you keep in mind it's few limitations.