6 out of 10 points and not recommendedprice, not much elseneed to use manual focus to get sharp images, no IS, needing to use f11 to get sharp images.
I purchased this lens a number of years ago to use on a film SLR camera and also used it for a short time on my 450D DSLR. If sufficient light is available and your subject is staying relative still you can get some sharp shots through using manual focus and f11. If it is dark and you dont have time to manually focus this lens is rubbish. I have since upgraded to a Canon 70-300mm f4-5.6 IS USM and this lens is far better.reviewed July 4th, 2010 (purchased for $250)
9 out of 10 points and recommendedprice, IS, sharpness at f8 and above, weightsharpness below f8
I bought this lens as a replacement to my Canon 75-300mm f4.5-5.6. I did a lot of reading of reviews of the Sigma 120-400 and the Canon 70-200mm (with and without IS) and ended up buying this lens. It might not be as sharp as the other lenses but I wanted a lens I could take hiking that didnt weigh too much on the off chance that I need a long telephoto. The sigma was heavy and the Canon 70-200mm wasnt all that long for taking shots of birds, so I decided on this lens. While I might not be as sharp as an L series lens, it produces high quality results, the autofocus can hunt around a little but is reliable and the IS is very useful. It may be pretty cheap in construction but if you treat it nicely it will give you good photos.reviewed July 4th, 2010 (purchased for $500)
10 out of 10 points and recommendedmacro ability, price, image qualitynot f2.8 through the zoom range, uses expensive 72mm filters, no IS
I bought this lens as a walkaround capable of taking shots of scenery and also for use with macro. It has lived up to my expectations. I use it on a canon eos 450d. The macro ability might not be as good as a prime macro lens but it is also cheaper and can be used to do landscapes. I have used this lens for portraits but its not a fast lens so the results dont have much bokeh. I notice that Sigma have just bought out a new optical stabilised version which will improve this fantastic lens.reviewed July 4th, 2010 (purchased for $350)