[CentOS] Setting up Linux File Servers in a University Environment

Hello Everyone

I work for a University Department that has a high number of Linux 
Desktop Users.  Currently we provide a users home directory via NFS from 
a file server.  Generally it works well for us, but I have been asked to 
look at our options for expanding the storage we have available.

So I thought one of the first things I had better do is consider are 
there alternatives to the way we do things now that could be better for us.

My initial research suggests that the only real alternative to NFS in 
this context is ISCSI or perhaps the combination of ISCSI and GFS.

So I was wondering has anyone on this list in a similar field implement 
ISCSI for home directories instead of NFS?  And if so would you be able 
to give me some idea of the costs/ benefits of doing this?

Thank you for your time and any insights you are willing to share.