The best highway view of Mount Robson is seen from this section of road (eastbound).
If you're driving westbound on a relatively clear day, I'd recommend turning around at the Terry Fox Viewpoint, also featured in this guide, and driving back towards Mount Robson, just to get the view.
Honestly, it's just that good! Truly one of the most memorable stretches of highway in the Canadian Rockies. Don't miss it!