I used my 935 to navigate a course today. I found the map-view pretty useless. It showed me only where I had already run and a little arrow indicating which way the Watch wanted me to go. That arrow was not to much help as it seemed to to whatever it liked.
With my old 310XT, I could at least follow a Little bread-crumb trail on the map. Is that not possible with the 935?
Oh yes, when starting the course the device restarted itself. That kind of thing makes me feel it is a bit unreliable...