[Steinar1]

Reinier, I have this lens on a Nikon D300s and it produces very good piqué over the whole range. The stabilisation works very well and I can easily handhold good IQ at low light conditions. There is a complete report on this lens using DxO in www.lemondedelaphoto.fr under "tests". Although it is in French, it is self explanatory. In all the reports I have seen, it delivers better piqué from 200 to 300mm than the Nikkor or the Canon issue. I can not say from personal experience how it will behave on FF, but check the reports. Kidly Vieux loup

PS I checked the report and it was done on a Nikon D700, so you should be able to predict pretty closely how it will behave on a 5D. http://www.lemondedelaphoto.com/Prise-en-main-et-formule-optique,5058.html