We have a similar setup in terms of student population. More offices, however.

We have a 20 Mbps, bidirectional connection, on fiber optics, and last Spetember students were maxing that out with p2p.

Some user education and some tweaking of the Cisco main router made things better. And, we are good now, but we've also been lucky in the fact that student body are not being too "bad".

As you cannot rely of users not using p2p (and you don't want to depend on that, of course), however, I am ready any time to have to resort to Packeteer, which is very good and very expensive. I mention Packeteer because that's what we use in our HQ, and I never looked at anything else. Packeteer will do anything you ask. But again, it costs a lot of money.