If you're copying Win8 to Win7, you're not going to be taking advantage of anything new in Win8. It's still going to use SMB2, and you've probably got SMB signing enabled which is going to slow things down a bit more.WTF? This is windows 8 to windows 7. How is this still a problem? Does anyone know a solution?
I believe Windows 8 will switch to the wired connection when you enable it. I don't think Windows 7 was capable of doing that... I'll need to search to back that up, but I do believe I remember that being a new 'feature' of Windows 8. (or I could be remembering something different, so don't take that for fact until I can verify it!).When you switch to LAN, turn off your wifi antenna on both machines. Windows remembers your first connection route to a LAN machine over SMB, even if a superior connection is found. It is very possible that you were copying over wifi both times.