[InvisibleMonkey]

Thanks for insights on NFS but…

I also found out the hard way that NFS paths do not like spaces in volume names when one of my external HDDs had a glitchy connection, I just changed the name to prevent issues.

I have spaces in volume names and changing that is not a viable option because of other system automation stuff. And I don't much like the Caffiene work around either. Really like to see SMB or AFP work as they should, and question I posted above about how common this is stands.

Well, YMMV, on doing a cat /etc/exports check in terminal the NFS share path showed up with a \ in front of the space, so I copied that in XBMC and it did connect for a while. Then it went offline again until I changed the name of the drive. It was a pain in the ass for the same reasons you mentioned, but my NFS connections are now both very stable. I also circumvented the need for disabling sleep or using caffeine by enabling the Wake on LAN function in OSX and XBMC and that also works perfectly.
I was in the same place you are but I'm glad I made the switch to NFS now, with a little tweaking it fixed all the problems mavericks brought to my SMB connections.