experience in bottom tier houses

Basically, in terms of sororities, the only difference is which fraternities with whom you have socials. Otherwise, the sisterhood, philanthropy, involvement and general logistics are the same. I would imagine the same is true for fraternities. I guess there's a prestige thing, too---if you care about that sort of thing.

Even if you're not in a "top tier" sorority, you will still have an awesome experience that many unaffiliated girls will not. Go all the way through rush and maximize your opportunities for the future. Even if you are not ecstatic about your houses left you'll have four years to find your niche, or a different house might snap bid you.

^^
I rushed because i wanted to be a part of something bigger, and give my experience at UW some purpose (which you can have without being in a sorority). I love my house, because I really just wanted to be in Greek Life. It's really all about the people.
Like the post above mine its about the experience, and you will still meet a lot of great people.

I don't think it matters a ton if you are a girl. It means you have socials with the lower tiered fraternities but you can still go to a lot of the tailgates or open parties for fun houses.

It matters a ton for guys. If you are in a lower tier house: you wont have many if any socials. Sorority girls will not come to your parties. Your physical house will suck. You probably won't have the resources to throw big events etc

Being in a lower tier house can be difficult and frustrating at times, because you're part of the Greek system but feel separated from it at the same time.
While it's definitely been a much different experience, it's still been just as rewarding, but in different ways. I've been able to have a real say in my chapter and believe myself and my pledge class have made a huge difference in turning our chapter around and pointing it in the right direction. Granted, it meant not having many socials and having to drag through university sanctions, it's still awesome to see that the effort I've put in could finally make a difference as soon as this fall.