So if you're having this problem (like I did) I just wanted to let you know what solved it for me.
I started the move and followed instructions here. I had about 77000 files and they copied at a rate of 140 files per hour. I pulled my hair 
What caused the problem was Intego Virus Barier, Real time scanning ON.
Turning Intego Virus Barier, Real time scanning OFF solved the problem.
Hope this helps someone.