We got home last night. As far as EA was concerned, things were uneventful - charging always worked. There was only one charger that someone had taped an "out of order" note to - easy enough to move over and use a different one. I didn't go up and down the line to see how many chargers were marked as inoperative. Sometimes the food choices at a Walmart aren't that great, but the bathrooms are always clean.
Going on a long drive like this definitely does warm the battery - at the end of the 2nd charging stop, ABRP was showing me that the battery pack temp was 107F, and I was getting the sweet 127kW charge rate when I first started charging (ambient temp was about 45-50F). So a combination of driving and DCFC are definitely warming the battery. After we got back on the road, I could see the temperature gradually drop back down to about 70F (easier for me to monitor while my wife was driving).
Mostly used the builtin navi for navigation, and for the most part it did a stellar job. The instructions are always clear and unambiguous. Any time there was a "weird" routing, it was because of an accident ahead that we could verify with google. That being said, there were a few glitches.
We had gotten off the NJ turnpike at one point to head to a charger - just after we got off the road, the navi suddenly recalculated the charging stops, and decided that we should turn around and get back on the turnpike - as a result the directions to the charger that we had gotten off the turnpike to get to disappeared - as it happens we knew it was at a Walmart about a mile up the road, and we could just wing it to get there.
Generally the choice of charging stops was pretty good - there were a couple that I did a manual override to find. At one point, the car was directing us to an EVgo station, but there was also an EA stop about a 100 yards away - it seems there are still outages such that the car navi isn't aware of all of the EA stations. I have already gone into the HERE map creator and added the missing EA stop - hoping that that will propagate out to everyone's car in a month or two. I suspect there may be more EA stations that the car doesn't yet know about - I wish there was an automated way to check the navi for all of them, and it really seems like VW ought to get the list from EA and do this themselves. That being said, I also see that there are EA stations that the car was aware of that are not showing up in the HERE map creator - somehow VW must be supplementing the POI.
A year ago when I first got the car, I did some tests at home - navigating to various locations to see how good a job of routing the car could do. Back then the builtin navi was picking L2 chargers at coffee shops or other such silliness - there was none of that this time around. The worst choice that it made was to pick a 50kW DCFC, and while that wouldn't have been bad, I also knew of 150kW EA stations along the way that would be a better choice. I suspected at the time that the car wasn't aware of all of the EA stations around the country, and at the time I assumed that as those POI got filled in the car would make better routing choices.
Perhaps more annoying, while we were on the GW bridge coming home, the navi made an announcement "Stay to the left for I-80/NJ turnpike". Which would have been fine if it had only said it once, but it seemed like it was stuck in a loop and it made the same announcement 20 times in a row. Eventually we got past that point - then the navi then seemed to get stuck in a loop of recalculating the charging stops and/or recalculating the route. Maybe a deluge of traffic info causing it to recalculate? Don't know. Then it seemed to get confused by the way that the NJ Turnpike has car-only lanes and car/truck lanes and kept giving us pointless instructions. Fortunately we already knew we were going back to the New Brunswick NJ EA stop that we had stopped at on the way up, so it didn't really mess us up.
Finally, once we left that charging stop, it was clear that we would need a bit of a top-up to get home. In my mind, I had already planned to stop at New Castle DE to do this, and didn't require instructions to get there, but the weird thing was that the car didn't automatically add a stop even though we clearly didn't have the range to get home without a stop.
We could have used ABRP instead of the builtin navi, of course. I used it a few weeks ago when we went to Allentown PA. But I find the ABRP voice cold and mechanical, and using ABRP like this uses a good amount of phone data, and I prefer the way the builtin navi zooms in when you get closer to a turn or a destination which makes it clearer exactly what it is that you need to be doing. That being said, I would sometimes cross-check the charging stops the car had picked by using ABRP on my phone.
Google maps is fine for shorter trips that don't require charging stops, or whether you have done the trip enough times that you don't require assistance in planning charging stops. But it doesn't have enough information available to make good choices for charging stops - ABRP plus a dongle is always going to be more solid than plain old Google.