I purchased the Tamrom because I wanted IS/VC and could not afford the canon 70-200 f4 IS.
The VC works great and I usually do not take it past 200. I do sometimes take it to 300 and get some keepers but I try to stay away from it.
Here is one at 282mm wide open. I am pleased with the sharpness in this image.

IMG_0032 by clemmb60, on Flickr