It's a judgment call. Do you feel comfortable riding with the level of traffic on the direct route? Would you feel comfortable on the longer route?

Most of my commute is on four-lane city streets, but most of my weekend riding is two lane roads. If either road has good sight lines, so the cagers can see you 1/4 to 1/2 mile back, and traffic is light enough that most intelligent drivers can get around you without slamming on the brakes at the last minute, go for it. If it's a twisty road, most traffic drives 50 mph, and there's skid marks every 100 yards at each curve, think twice.