I've been doing this for over 6.5 years, since before the Nav even had the ability to pick Superchargers. This "Beta Trip Planner" feature, which tries to pick your Superchargers for you has an awful fatal flaw that has bitten me and several other people, so don't blindly trust it.
The fatal flaw is two-fold:
First, whoever programmed it set the preference to be "fewest stops possible" and all else be damned!! So it will have ridiculously long charging times to go up near 100% full and then driving down into single digit % just to try to skip over Supercharger stops. It's insane and not a good way to travel.
And the second part is that when it has chosen the Superchargers it wants you to use, it HIDES the others along the way off the map! That can really catch people where they don't see any other fallback options in the middle because they are hidden, so they are gritting their teeth and white-knuckling to make a really long stretch happen that didn't need to be that way.
My car gave me the recommendation to charge up to 100% in Grand Junction, CO and drive non-stop to Silverthorne, CO, arriving with 7% left. That would already be crazy to begin with, but it was winter and below freezing and all uphill! So there was me, driving about 50 mph on I-70 with minimal heat to make this work because I didn't think I had any other choice. I only later found out there was a Supercharger halfway in the middle, in Glenwood Springs that the car had hidden from me that would have made it easy.
So I will sometimes plot a whole trip at the start, just to get a look at what the ballpark of the whole thing is going to look like, and sometimes here and there on the route, but if any of the stops look questionable or a charge time over about 40-50 minutes, it's probably doing something wrong, and I will cancel it and zoom out to look at where the Superchargers actually are to see if it's skipping something and making it unnecessarily difficult.