Impossible to choose just one lens, I don't really get the point of the question.

The new 400mm f2.8 and a set of the new x1.4 and x2 TC's. Now that would be as good as it gets for me! Just a shame I won't have the £12k that it would cost!

Even with the weight reduction of the new version I still reckon it'd be too heavy to walk around with all day. I think I'd go for the new 300 f2.8 - it's lighter and only £5600The new 400mm f2.8 and a set of the new x1.4 and x2 TC's. Now that would be as good as it gets for me! Just a shame I won't have the £12k that it would cost!
hollis_f said:Even with the weight reduction of the new version I still reckon it'd be too heavy to walk around with all day. I think I'd go for the new 300 f2.8 - it's lighter and only £5600
shane1980 said:Nikon 14-24 best wide angle lens on Market
Then again the nikkor 24-70mm
ziggy©;3713370 said:On a 7D?
forkie said:If u could have any lens for you’re 7d no matter the price what would it be
And why?