As to macro photography...
Well to be honest: I only shot around 25 of 3000 pics with my macro in NZ. Mostly shells from clams and snails. See http://www.flickr.com/search/?w=3891211 ... and&m=tags
But many of them were large enough to capture them with the 18-200mm at magnification of 0.2 and below. Just watch out to stop down to f8 or f11 to improve the close-up picture quality and depth of field of the zoom.
So it was not really worth it to carry the heavy 105mm VR with me all the time.
To decide for yourself: just consider, what you normally shoot with your macro lens...
Thomas (beware: Nikon-fanboy and moderator!) My Lens Reviews
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