See my comment about re-inventing TCP poorly when error detection/correction and re-transmission are added to something built on UDP. As I said NFS has a lot of baggage along with some nice features, its all about using what’s appropriate to the application and the target environment. I’ve pretty much always been in mixed Windows/Linux environments (with Windows machines dominant, so any compatibility stuff had to be on the Linux side by default from the system administration overhead alone) so SAMBA has made more sensed to me than NFS.
As to ramdisks, if the communicating processes are on the same machine, its hard to beat shared memory and semaphores for IPC.