Annoying File Opening issue with SharePoint Designer 2010

Really annoying feature or bug with SharePoint Designer 2010.  

Sometimes files not refreshing properly and not loading the latest copy saved in SharePoint and also displaying erroneous checked out/in status.

Loads of other people also found the same problem eg here

http://www.tompuleo.com/2009/04/sharepoint-designer-says-i-have-file.html

Found that even clearing the cache folders did not work.

C:\Documents and Settings\username\Application Data\Microsoft\Web Server Extensions\Cache

Win 7 

C:\Users\username\AppData\Local\Microsoft\WebsiteCache

Check in and Check out status still not working.  Latest saved file loads from SharePoint however, it seems like a Control->F5 should also be done by navigating to the folder of where the file is sitting in Designer 2010's navigation node.  At least the latest saved file seems to load.

Made sure all SharePoint Designer settings turned on the Site Collection Admin section.

But the problem does not seem to happen when it was installed on the Server that the Test SharePoint farm was sitting on... ummm

Tried adding SP2 for Designer 2010 to see whether it fixes it.  But still to no avail.  Check in and check out status still erroneous.