I went to the psychology one last year and I didn't find it that helpful. I would have preferred to use that time studying solo. I think I was annoyed because the majority of people took it to be a social occasion with their friends, and spent more time discussing what type of coffee they were going to buy from the booth than paying attention to the lecturers.
The notes they gave at the lecture were pretty good though. I think these notes are good for cementing the basics and pinpointing the types of questions likely to come up in the exam.
9 hours is a really long time. I found myself zoning out after lunch, so I practically wasted those 3 hours.
Conversely, my friend also went with me and she found it really helpful. So I guess it depends on the person.

Looking back on this post, I realised it's a bit topsy-turvy, but hopefully you can extract some useful information from what I've written.

edit: I went to the TSFX lecture.