We were there on a cold day in late November in 2023. It's huge. And, for its size was pretty empty. It very much could have been the season and the cold weather though.
It's basically a full day's commitment as the trains take a couple hours each way. I don't know how the Berlin-Hamburg line closure would affect this line, but as they frequently go to Hannover after Wolfsburg there's a potential these trains could be busier than usual. (I'm sure Mark from Schwerin has better info on this than I do.)
TBH, I didn't love it. I felt like it wasn't really enough to do. There are (or were) add-ons to add-ons to do the more fun extra stuff and they conflicted timewise. And, not all the factory tours are in English. If you miss the English one they don't want to let you on the German one, for safety reasons, in case there's an emergency and you don't understand the directions.
However, since it's almost two years later and summer, they could have redone things and the exhibits are more dynamic and refreshed.
My husband is the bigger fan and he enjoyed it more than I did. I liked the car displays. They're got some pretty cool one-offs.
The cafeteria was really nice, food was decent, whole place was very clean, there were lockers for stuff. The gift shop prices were eye-watering, but they had good stuff, not junk.
(husband has had: '57 oval window softtop, 71 super beetle, 2 microbuses, don't remember the years, and I had a Jetta VR6 when they were still fun to drive)