Extracto: A little sharper and better color contrast than my old 100 f2.8 Macro. I'm hoping the IS will make the swap worthwhile. This lens has a 67mm filter so you have to buy a Canon 'macro light' adapter to use a Canon ringlight or dual macro light. I would give this 5 stars but the cheap feeling plastic construction with a lens in this price range just doesn't work for me.
Extracto: This prime lens is sharp, well constructed, and versatile. I am enjoying great results with both portraits and product shots. It is heavy enough to remind you of its quality without being cumbersome.
A favor: Easily Interchangeable, Fast / accurate auto-focus, Nice Bokeh, Strong Construction
Extracto: I have so far tested out this lens on some product photography and wedding like detail ring shots. It is a great lens, beautiful detail and I absolutely love the colors it produces. Like others have said it can be slow to focus and 'hunt and peck' if in low light, but if you can find a harsh edge for the lens to focus on it usually does alright.
Extracto: About what you'd expect from a prime L-series. Very sharp and smooth manual focusing. My only complaint is focus-search when going from macro to distant or vice versa. You can set the focus range, which is nice, but on full-range focus it's touch and go. This is a minor gripe..
A favor: Consistent Output, Durable, Lightweight, Nice Bokeh, Strong Construction
Resumen: Focusing can be slow if you expect the lens to go from one extreme to the other of its focus range. Therefore it is better to adjust focus manually to near the focal range you are working at before using auto focus. Then it is quite quickManual focusing is better at the macro distances.
Extracto: A fine macro lens that's also useful for portraits. I don't use it as much as I thought I would, but merely because I don't have occasion to use that focal length, and I prefer the 85/f1.2 or 50/f1.2 for portraits.
Extracto: I wasn't sure about this lens at first since it seems more plastic than the other L-series lenses I have purchased from Canon. But the images are sharp and despite the noise of the auto-focus, it appears to be good quality glass. Makes nice portraits and I am enjoying the sharp macro feature.