I've noticed this also .. BearShare does seem to be the most polite client out there. Just from observation of uploads, it seems to quickly figure out how many slots it can grab and queues requests at *its* end. Hence as soon as one upload completes, the next starts (or joins the server-side queue).

LimeWire's not as friendly - if some smart alec requests a hundred downloads at once, it can fairly hammer away at it's target server.

Morpheus seems to be the worst - I've noticed morpheus clients requesting each of 50 or so files once every 5 seconds. Ikky bandwidth drain.