Hi
sorry- dont have any news regarding a free reliable vmdk-reading tool.
For readonly inspections of vmdks with dubious or unknown content I highly recommend the latest UFS-explorer in trial mode.
When I need to write vmdks or want to extract data I tend to use a LiveCD in a WS or ESXi VM.
Last time I used vmware-mount I had launch an admin-cmd, run the mount command and then had to view the content from cmd with dir X:\ and so on.
Allways worth a test is WinImage - sometimes even 7zip does a good job for a preview.