Broadband-over-Powerline Experiences?

tarp asks: "I'm moving to the City of Manassas, Virginia, where ZPlug offers BPL (Broadband over Power Lines). The city was the first in the nation to offer BPL as an alternative to DSL or Cable. They claim a 300 to 500 kilobit per second connection speed, and rock-solid performance since the only downtime would be when the power grid goes down. BPL is also rolling out in other locations, despite campaigns by amateur radio enthusiasts to stop it due to interference. Anyway, have any of you used BPL, and is it something I should try rather than getting a DSL or Cable connection?"