This works well on the Edge 500 also. One doesn't have to follow the breadcrumb course as it can be specified to give a warning prior to the turn. I enter 300 feet as the preferred warning distance. Then, no matter what screen you are on, there will be a small box at the bottom of the screen stating "turn right" or "turn left". If there is a T junction, and you the route takes you straight through, it will state "straight" in the box.
It is imperative that you go to the "Do Course" prior to starting the ride, especially if the course is a long one. I have had the Edge 500 shut down when trying to navigate through the breadcrumb screen. I had to divide the course into 2 or 3 parts to keep it from being corrupt. By doing course, then scrolling through the screens, you can see if it will function properly. Then go to "Stop Course", and when it is time to do the ride, go back to "Do Course.
Still, as DrPete says, well worth a donation.
+1, and I do the same for long routes that may have many turns in it--2 to 3 sections for each century or century+