Which is the better zoom lens?

[birbajans94]

So recently upgraded to a full frame camera, now I’m looking to add some glassware. I’ve been looking at the 17-40mm as well as the 16-35mm. My main question is what’s the major difference(if any)? As well which would you recommend for all around shooting?

[ebiggs1]

"The "III" version is reported to be significantly better than the previous two."

I certainly hope so. I have the II version. I replaced it with the Tokina AT-X 16-28mm f/2.8 Pro FX Lens.  I am not a Tokina lens fan but this lens is fantastic. It is my only Tokina and likely will be my only Tok.