As someone who has gone to a (kinda) similar medical conference for work, I would probably say, based purely on my experience, that it's not really worth it. I went to a Hospital Medicine conference since I work with hospitalists regularly, and while many of the breakout sessions had interesting information, I don't know that they are worth it when you have so much training to go to truly grasp their impact or affect your clinical choices. A lot of the information presented was about the different organizations that sponsor the conference, awards given out, and small clinical vignettes that are either just snippets of research, or things that I didn't understand the full impact of.
Although I was still just applying to schools at the time that I went, I can't imagine that 5 months of pre-clinical education would make much of a difference in terms of making the material more relevant/relatable, but I could be wrong.
However, its entirely possible that your surgical conference will be very different from the Hospital Medicine conference I went to. Maybe it will be more relevant for a medical student than mine was. The other reason that could make it worthwhile going is to begin networking. I am not very good at meeting new people, especially when I'm by myself at a conference full of established physicians and I'm nobody to them, so I met next to nobody. But, if you are more of an outgoing person that can make connections with people you meet there and begin your networking early, I'd say that could certainly be a strong reason to go. As the adage goes, 'it's not what you know, but who you know' and if you meet some connected surgeons early in your career, it could help you later on.
those are my 2 cents. Hope whatever decision you make works out for you!