Sigma 18-200, tamron 18-200 or nikkor 18-135 for D80?

hi,

I have decided to buy D80 but not sure yet which lens I should buy.
I need a flexible lens for traveling that takes sharp pictures.
nikkor 18-200vr out of my budget.

any suggestionsf: sigma 18-200, tamron 18-200 or nikkor 18-135?
Thanks

Marcin
7 answers 7