I don't have any direct experience from prepared student reviews but I would think that a small study group that you discuss what you've learned, clarify what you don't understand and quiz one another >> prepared student reviews/talks. That being said, if it is at your school, free, short in duration and hosted by very intelligent students, it certainly wouldn't hurt to try it out with the mindset of leaving if it's not helpful. If you need to listen to some integrative lectures, I would recommend commercial Step 1 review videos like Pathoma, DIT, FA Express, Kaplan, ect.
Yeah I am already signed up for DIT and just wondering if I have time for another review as my study schedule is packed as it is. Plus this is the first year my school is doing it so I worry how well it will be run.
The best people to ask for advice is your classmates. They will have a feel of whether it will be good or not and will have an opinion if self-study/DIT/Uworld would be a better use of time. Consider if you will regret not going if your classmates say it ended up being awesome.
Things to think about:
Are the students putting it on doing it to truly help or are they trying to charge and commercialize it to make money? If they're doing it for free then they might use the best available resources and have no limitations of using copyrighted material or saying things that commercial reviews could not say. For example, "on my test they asked the question in this way", "book/Qbank A sucks, use book/Qbank B", "Goljan explains it this way, Pathoma explains it that way". Again, it goes back to their motivations, are they making their own presentations/study guides attempting to be the next commercial review company or are they using the best available resources in a casual/free environment (FA, ect).
Again, this is all speculative by me and the best people to consult is your classmates.