That's the wrong question. It sounds like you've already made the decision and want to hear anecdotes that validate your choice, and you'll probably disregard

That's the wrong question. It sounds like you've already made the decision and want to hear anecdotes that validate your choice, and you'll probably disregard the survivorship bias (explicitly asked for successful examples) and participation bias (hacker news users voluntarily answer). What you should do is look at some numbers -- % of friends vs nonfriends founders that exited successfully, perhaps. After that, I suspect the question you will want to ask instead is "How do I find a good cofounder outside of college?"