[CQ-Contest] Any Experience with HomePlug?

[Eric Rosenberg - W3DQ]

I need to expand the network (vertically to the main and second floor) 
in my old, plaster-and-lathing house.  I can't run Ethernet... too much 
destruction would need to take place, and wireless simply doesn't work.

All that's left is HomePlug.  The ARRL says it's (relatively) 
interference-free. No one has talked about performance, so I'm asking of 
you have experience with this technology and what it has been.

Thanks,

Eric W3DQ
Washington, DC