pros and cons

I promise you, if you're looking for a real sisterhood you'll find it. Most people don't care whatsoever about "rankings" (although I won't lie and say pretty much everyone, in a sorority or not, cares about what other people think of them). Yeah there will be at least a few people in every chapter who want to climb the rankings or maintain their position or whatever they think will make them feel better and look cooler, but I think most chapters aren't like that. But some chapters are full of those people though (and you might be able to figure out who), so you'll want to avoid those.

But seriously, feel it out during recruitment. If a sorority has a genuine sisterhood, you can feel it in the room even when you're just sitting there talking to one person. That's what you want.