Hi,
You can download the full resolution tiff images at this website:
http://www.tamron.com.hk/A011/
I look at the samples images and compare to my Canon 400mm F5.6L + 1.4xTC (@560mm F8), the Canon 400mm F5.6L + 1.4xTC still look a bit sharper and less CA at wide open, but Tamron look a bit sharper when step down. Now the questions is: will the real world copy give a similar IQ as these sample images?
Anyway, I'm looking to change to a zoom lens (want to learn to do some video) and this look like a good alternative if there is no Canon 100-400mmL II in 2014... I don't might if the lens built is not as good as the Canon L (I don't "qiong" and always use it with care) and AF not as fast as Canon L (I seldom shoot BIF), but the lens must be as reliable... hopefully.
Have a nice day.