SharePoint 2010 COM SaveBinaryDirect not reliable

I've recently found that the SharePoint 2010 client object model is not reliable. Calling the SaveBinaryDirect method was working fine for weeks until it started throwing errors. I looked up these errors and found no help. One of the errors I was receiving was "The remote server returned an error: (409) Conflict." Because I was unable to find any information about this error (that was relevant - there was no conflict), we decided to rather create a custom net.tcp service to handle the bulk document uploading.