Given that you've got a 2.5mbps connection speed, excellent or turbo LW connection, no firewall then I don't know what else it could really be.

Did you try the optimising tips? What do you have your LW speed set at (cable/dsl, T1, T3)?

Lots of ISPs do use traffic shaping when it comes to p2p, they justify it by saying that people who use p2p are hogging bandwidth. Do you know anyone else who uses ihug & LW? If so, do they get a decent download speed?