international reputation

Is it really beneficial in the long run to join one of the four more well known sororities? Do girls in those four have more advantage in terms of networking? Do they have a stronger alumni presence compared to the rest?

There are pros and cons, if you don't like the girls in your chapter then you're wasting your time, but it does put you at an advantage being part of the greek system in general. By joining one of the larger sororities internationally, you will have access to a larger alumni network post graduation. I know of many girls in sororities who have gotten jobs from alums across the USA and Canada.

Join either DG, APHI or KKG.

KKG and APHI are usually middle-top tier and DG is usually middle.
They are all very famous internationally though. KKG and APHI have a lot of chapters around the US.

Im from america, a southern big sorority type school and the most highly reputed international sororities that UBC has is ADPI, DG, Kappa, and KAT. Those sororities are usually top tier but can rarely be middle at a lot of american schools, especially the south where joining a sorority is a HUGE join or die moral. Alpha Phi, Gamma Phi Beta, and AOII are also good too but chapters tend to be middle tier with a few top tier. In the states you don't here much about Alpha Gamma Delta, most people don't even know who they are. But by all means don't join a sorority based on that, join a sorority that has a good reputation at UBC and has a great Alumnae Association.

If that all your interested in then don't go through recruitment. We don't want you.