JT wrote:
.... I just thought there might be a specific reason why one route would be recommended over the other. IOW, maybe one of the mapping programs has more current highway data?
Most of these programs give you the 'fastest route'. If you choose 'shortest route', they probably will give you the same optimum - unless one chooses to use some surface street or cow path. But to compute 'fastest' they also have to make speed estimates on different segments.
Sometimes speed estimates are based on traffic data, but more often it is just a function of the road category. Different estimates can produce different times.
But a program like Google Maps gives a couple of a alternatives. It is also easy to modify a recommendation to use another road. Often I find that the differences in time and distance are minor. I really have to go out my way to make big changes, especially on long routes.
Sometimes road construction makes a difference in recommendations. Last time I looked at Phoenix on GM, there was work at the I10/101 intersection. If one program takes into account a newly opened interchange, it might give different times. Usually the best source for up to date road information is the state DOT, their traffic alerts, traffic maps, and webcams.
correction - it is the I10/303 intersection that is currently under construction. 303 is an outer beltway. When done it would give you yet another choice.