An excellent macro lens. It benefits hugely from being stopped down to at least f5.6, but from there to app. f16 it's wickedly sharp! The contrast is excellent all the way. To me the lack of USM isn't a problem - I never use AF when doing macro photogaphy anyways (besides the AF speed on a dSLR isn't THAT bad). Apart from being a great macro lens, it doubles as a portrait lens as well.