Okay So I spent a few hours playing this course. Did all the available events, plus the circuit experience.
Had the most fun with the WTC600 event -- my challenge to you guys: try to win it with the Tesla, any setup! Pretty fun and challenging! Chasing down the 911 GT3 in a 10-year-old Tesla is NOT easy, but it is doable. I won by about 4 seconds.
However, I had a LOT of trouble with the 950PP Gr.1 Prototype event. Eventually won it with the Red Bull Junior 2019 car, on RMs, FM1, slight ballast and slightly reduced power (I think about 96), to get it under the PP limit and fuel efficient enough to only pit once. But it was tough. I didn't have any room for serious error.
As for the track itself:
A+. Once you get those turns down, it actually has amazing flow. Some of them aren't super intuitive, but the circuit experience helped me work out optimal lines and brake points to really enjoy the course, and I love the extreme changes in elevation. (hint for the circuit experience - use TCS 0, and avoid second gear).
The visuals are an A+ as well. I get that this is a piece of nostalgia for a lot of people, but friends, the old Grand Valley looked really boring and generic. This new version is stunning, just a tremendous improvement. Also, I suppose I must have my screen brightness turned up higher than other players, because I had zero trouble seeing the road in the tunnels.
As for anyone who says it's not the old Grand Valley, well, yeah, that's definitely true. I'm fine with that though.