ok well, i have been at two high schools, which we have run both macs and PC for the arts department.
they have used from GIMPshop to Photoshop on old and new macs
we did have a G5 server which was when we first got the mac lab, but since that we ditched it and it connected straight our windows server 2003 system.
connects with AD so it allows redirection to there home folders proxy settings and all that.
there are a few flaws which kinda a hassel.
the user has access to the local drive (great for saving stuff and not on the network) but sometimes these folders come full of junk, and other users are unable to save their work.
my partner did set up a script to do that but i was unable to catch a glimpse as he did. it was in the cron file. this allowed our staff members (arts, film and tv) to have admin access to the drive and delete the junk.
but other then that it seems to be a good way to go for arts. but its all on personal pref.
having a mac server would help you could save you a lil bit of time having it on the same network with different usernames you could set it up like that but could be a pain thats all.
Cheers
Paul