Here is what I have. 2010 Mac Airbook running OSX 10.8.2 connecting to a Windows2003 SP2 server over a good WAN connection (site to site VPN over a 25/10MB Internet connection). I'm also running Win7 and Win8 via Parallels 7 on this Airbook. When I transfer a 256MB file to my Windows server using OSX it takes about 5 minutes. When I transfer this same file to the same server using Win7 or Win8 via Parallels it takes less than a minute. I also find browsing file shares to be very quick with the Windows instances but quite painful with OSX. What gives? Are there any settings in OSX that could help speed things up?