Nikon 18-200 VRII vs Sigma 18-250mm f/3.5-6.3 DC Macro OS HSM

My fiance has a D90 we got her a year or so ago. It came with the 18-105 nikon kit lens. Not a bad little lens. When we need more focal length like shooting wildlife I have extra glass she can use. I was thinking of getting her a walkabout lens with a little more mm's to it. She likes to shoot her grandaughter, photos on trips, etc. At times I see her trying to get a close up of a flower or bug on a flower.

I tend to prefer Nikon lenses but happened to see the review on the Sigma. Can anyone give input on one vs the other? The sigma looks nice on paper, but...

The Sigma has minimally more reach, and can min. focus at .35m for macro vs the .5m for the Nikon. The review on the Sigma talks a lot about the pin cushion distortion as well as flare and Chromatic abberation. Both seemed less on the Nikon...

Price wise, I think they are par...

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Harris
PBase/DPReview/NTF supporter
Egret Stalker #4, WSSA #29
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