I have had some issues with Windows file sharing between a desktop Windows 8.1 based PC and a Mavericks equipped Mac. I even wrote an article about it on another site: Fixing Windows & OS X Filesharing Slowness (SMB2).
Since then I have reinstalled the desktop PC with a fresh install of Windows 8.1. Without the fixes mentioned in the article I linked above. I also tried transferring files using a beta version of Yosemite and it seems to work much better now.
I still use the same network and infrastructure. So if you have SMB issues with your Mac and Windows computer. Maybe try upgrading to Yosemite when its released, or be brave and test the free beta version.