ML and SMB share problems

I've seen a lot of posts on many different forums for Snow Leopard problems connecting to SMB. In particular, files disappearing. I would like to know if this is still a problem people are experiencing with ML or if my problem is unique to my environment.

The symptoms for our environment: One user can upload a pdf to a share and another user occasionally cannot see the PDF in that share through the finder (both users connecting via SMB and both users running 10.8.4). However, if you navigate to the share via terminal (on the computer that finder can't see the pdf) and issue an 'ls' command, the file appears. What is happening with the finder that causes this?

If you disconnect from the server, then reconnect to the share, the pdf will show in the folder for both users. The problem is sporadic too. It doesn't consistently happen with the same users.

The file server they are connecting to is a Windows 2012 Storage Server. It used to be running a trial version of ExtremeZIP, but that has since been removed so all users are now connecting with the same protocol (smb).

Any help or guidance in resolving this would be greatly appreciated.