Whats wrong with the Nikkor 70-200 4.0 VRIII ?

The only problem I can see is that this lens is brand new so availability is low.  The price is too close to the 2.8 and let's face it.  We all know the price will drop over the next few months.
So you'd have to be absolutely desperate for the f4 to get it now at this price rather than either wait for the price to fall or just go for the Sigma f2.8/used VR1