We had a NFS share first, but the NFS files-system creates temporary hidden files like ".nfs0123123 " by which our build jobs got confused. When there is an inventory process running, getting a list of files, the .nfs0123123 files are included in the list. When the ZIP operation runs to pack all files together, the .nfs0123123 file was already gone, which led to an error in the ZIP operation.
We have Ubuntu 12.04 LTS running and did some comparison between NFS and Samba and found no big difference in terms of performance. With Ubuntu 14.04 LTS and Samba 4.1 we expect a performance improvement by using SMB3 instead of SMB1 protocol.
I cannot believe that a shared disk feature is not available on the VMWare server side 
Thanks,
Michael