Talking to current students can be super helpful, BUT I would probably not make the decision based on culture alone.
FWIW, I spent my summer at a big tech company in the bay area and met a few MBAs from Sloan. I felt good talking to them and continue to stay connected with two of them.
In all honesty, look, they are all the same people. The cult-ish culture thing happens AFTER you go to school. It is not a self-fulfilling prophecy. International students in Ross suddenly start to say GO BLUE (Football culture or any college sports culture does not exist in India) and start talking about action-based learning. I think MIT will induce the same innovation-focused leadership etc in their students, similarly.
So my advice is, go ahead and start to get a feel of the culture but talking to a few students would still be 1-2% of the entire class. All schools have the same people - some extroverted, some introverted, some overachievers and some laid back folks. You cannot go wrong with either me, but if I had the same choices, I would pick Sloan.