I think an F2.8 lens is very good
The Tameron VC you refer to Kai what does VC refer to? Is it a vibration reduction lens that lets you take advantage of the Nikon VR technology.
I was thinking of getting a Nikon 135mm F/2 which is not a zoom lens but it got a review which said it was awesome. I guess there is no single great lens, otherwise they would only make one type.