I too have seen many negative comments about the 18-105 and they are almost always negative simply because it is a "kit" lens. I personally do not care whether or not a lens is a "kit" lens or a "pro" lens. All I care about is the results, and from my experience this lens is just fine for a travel lens, sharp, lightweight and a decent focal length.
Good luck and enjoy your travels.
Marc There are always two people in every picture: the photographer and the viewer.-Ansel Adams