I'm not sure you need to agonise so much over this question...!Of the three lenses (18-105mm DX, 24-120mm f/3.5-5.6 and Sigma 18-200mm), I would expect the 18-105mm to produce the best results under average circumstances. It's the one I would choose for a trip You might like to check out out Nikkor Lenses Forum for more information on that part of your question.
Copyright © Nikonians 2000, 2014
All Rights Reserved
Nikonians®, NikoScope® and NikoniansAcademy™ are trademarks owned by Nikonians.org.
Nikon®, Nikonos® and Nikkor® are registered trademarks of Nikon Corporation.