On cars with supercharging, the range assurance ONLY uses Superchargers, despite the display showing non-supercharger points you have used before.
This make it pretty useless anywhere outside the few areas with dense Supercharger coverage - it will send me on a 100-mile detour to visit the only supercharger in the area when in fact I've got just about enough to get home and my natural route passes several fast charge points where I could stop for 20 minutes if I needed to.
IMO, the emphasis in the marketing was all wrong - the Range Assurance announced with huge fanfare, blog posts, articles placed in the press etc. is actually almost useless - in dense supercharger areas you don't need it, and in sparse areas it makes silly suggestions so often that you will fail to notice if it's ever being helpful. On the other hand, the route-based charge graph (introduced in 6.1 with not much publicity) to me is a HUGE improvement in managing range and avoiding range anxiety.