The only way a lens has different settings on the camera is for fine tuning and since you have that off, in your case they are all acting with the same settings.
FWIW the 18-105 kit lens tests out pretty well for sharpness especially for a "kit" lens. I do not have an 18-200 but have heard so many negatives comments regarding the lens being soft especially paired with the D7k. For my own travels (vacation not specifically for photographic reasons) I typically bring my D7k with the 18-105 and then bring along a 50 f1.8 just for night shots simply because it is small, lightweight, easily fits in a jacket pocket, etc. I have rarely missed having a longer or faster lens. The speed at which it acquires focus is usually fine for travel shots. For me I would rather give up the extra reach for sharper shots in general.
Marc There are always two people in every picture: the photographer and the viewer.-Ansel Adams