Way too many factors involved to give a real answer.
For example, if you are shooting a landscape and pointed east, you might get a colorful sky before, during and after dawn, but the landscape will likely be very dark. In that same location, if you are shooting west, it will probably be dark before dawn, but as the sun comes up you start to get nice light on the landscape it self.
And of course, some landscapes might look better with side lighting, so they might be best shot looking either east or west (assuming, for this example that the sun is directly east-west).
Some scenes don't recieve much light at all, until a few hours into the day. For example, big hills and mountains. Their western faces may not get any good light until after mid-day, and the sun may 'set' behind another hill or mountain long before it would set over a flat horizon.
If you have a good idea of the location and direction of your scene, then you should be able to at least guess at which time will give you the best light on the scene (or maybe the best chance of a good looking sky)...but any landscape photographer will tell you that it takes a lot of perseverance and/or a lot of luck to get THE shot.