NFS basically breaks the client computer until the host responds, while SMB detects the I/O error earlier and, at least, doesn't hang the terminal.
Other than that, SMB allows for permissions and a bunch of other features. It is, basically, a more modern and robust protocol. Does NFS shine for some use cases? Indeed. Would it be the first choice for most ones? Nope.
Disclaimer: my sysadmin skills are not so great, I'm talking as a user
Soft mounts report errors immediately, hard mounts hang.
And for permissions, NFS provides everything under the sun that you could possibly need via ACLs. NFSv4 is a very modern protocol, much as SMBv2 is (not SMB though, it's awful).
Linux has had NFSv4 for what, 6 years now, at least, and even v2 and v3 had some limited ACL support?
That's nice to know, it seems that we have the "hard" configuration at the lab and it's a real pain. Backwards compatibility, you know. For my mini-cluster we use SMB and couldn't be happier.
1) The caveats of NFS can be crippling if you are a rubbish sysadmin. NFS requires a more thorough understanding than what you can get from a tip sheet.
2) Samba is single threaded, performance will suffer serving SMB from a Linux machine. For this reason it would be better to serve SMB from a Windows machine.
3) Using a foreign protocol between homogenous computers when the native protocol will do is non-ideal. NFS is the right thing when sharing filesystems from Linux to Linux.
If you use any NAS device with a weak CPU and you have a choice of CIFS or NFS, the NFS transfer rates are normally 25% faster and the load is much less on the server.
I believe NFS is a less chatty protocol with fewer roundtrips. SMB is not a particularly well-designed protocol overall.
My only evidence is anecdotal. Back in ~1998 we had Samba running on our small Linux file server using Windows NT desktops via 10mbit Ethernet. It was dog slow, not just for browsing but on sequential things like file transfer. We installed NFS mounts on the same box, and it turned out to be lightning fast. I don't remember just how fast, but it made everyone go "wow".
Nowadays, with NFS over fast 100mbps or gigabit Ethernet the latency difference probably is not significant enough to make a difference. I prefer NFS just because its more Unixy.
I third this. I was attempting to set up my Raspberry Pi for sharing a big HDD that was plugged into it on my home network, and the NFS mounts appear to weigh lighter on my vanilla Raspbian setup.
And fwiw, if there's some sort of error with the mount, the terminal lets me know right away.
More details would be nice.