I had the same situation with 34 student client iMacs on 10.8.4 connecting via Remote home Directory , Open Directory to a 10.7 server on a mini. Everything seemed to run fine, although there were occasional timeouts on logins. (which I believe I tracked back to the Permissions settings when adding new users. AFP - needed to be added at the group level for easier setup) We ran this way for a couple months, I updated several of the clients to 10.8.5 as well. Finally, with some of the supposed fixes in 10.8.5; I upgraded the server one night and everything still seems to run fine. Even all Adobe CS6 APPs ran fine, except Illustrator, which never seems to like R Home Dirs.