I also have all boys, and my husband was in a co-ed business fraternity, but not a social fraternity.
I have mixed feelings about my boys joining a fraternity. I would love for them to have the friendships and bonds that a fraternity brings, but no way do I want them to be hazed (my definition of hazing is not necessarily the same as the official definition). My oldest son's godfather is a Phi Kappa Tau and already talks about the day my son pledges.
I do want them to go find a nice AOII girl to get married to, though!