Can I slide in on this one, although my problem is slightly different
Starting point is D80 with 18-135 kit lens, which I actually find excellent, but presumably worth next to nothing S/H
So do I also go for the 18-200 which no one has a bad word to say about or get a bit more reach and bit less overlap with the Nikkor 70-300mm AF-S VR IF (or put in a bid for your Sigma 70-300, VB)?
I don't mind a bit of lens changing and don't want to go to prime price/weight.