Summary: I have to say.. I had a hell of time deciding between this lens and 50mm f/1.4 USM lens. The obvious differences were of course the lack of the USM and narrower aperture of f/2.5. So, if you are thinking about buying the walk around lens or needing the lens capable of shooting in low light situation, this lens is not for you. Other than that.. I think this lens has very specific usages and when it comes to that it does a superb job. Most noticeably, like any other macro lenses, it takes fantastically sharp corner to corner macro shots. Its 0.9ft of minimum focus distance is 0.6 ft lesser than 50mm f/1.4 lens. This is good if you really want to get closer to your subject.

It works really well as a portrait lens too.
However, due to a slow auto focus speed, I recommend that you use this on a static subject.

For the price and the performance (as long as you know how you want to use it), this is a great lens.

Summary: I have found this lens to be very useful for my photos of objects and or items I sell to consumers. The detail that the lens picks-up is unbelievable and is very helpful to my clients when reviewing pictures of their purchases.