I did one last year (33 in a 30 zone where it changed from 40 and i braked a bit too slow)
It was pretty boring but not awful and too 3 hours online
Everyone had to participate and one chap was caught doing it while actually driving!!! There were some real dickheads on there who just wanted to argue that they shouldn't be there
The other issue was that the bloke running it seemed to have an issue that I had an electric car and with all the automation on it - he kept saying that I shouldn't use the touchscreen even once I explained I had mostly voice command or set ups on the steering wheel buttons. He also made a few comments about electric cars in general that i don't think were relevant.
I don't think I learned anything though, I appreciate i was speeding so no argument from me about doing it but I am a really good driver generally and have done some advanced courses so I already knew what he was saying. I just answered when asked, kept my mouth shut the rest of the time and made sure I was even more careful going forward