Is your camera a Canon?
I preferred 35mm and 50mm primes on my 40D but on the 5D the 24-105 is my walk around. My Canon 24-105 is pretty sharp at the wide end and less sharp at 85mm and above, or somewhere thereabouts.
For a trip where you'll be photographing scenery, landscapes, and portraits the 24-105 is probably a better bet than the 24-105. In those situations the only advantage of the 24-70 is better bokeh at f2.8
One note about the 24-105 - reviews on it are hit and miss, there is probably more variation between production copies than there should be.