Windows updates on Citrix servers
We are currently running Citrix 4.5 on server 2003, we only have two units but this is likely to be increased. When this system was installed roughly six months ago the company suggested avoiding installing Windows updates as they had a habit of upsetting Citrix and so we should rely on AV software. I'm not very happy about this situation as we use WSUS to update all of our other Windows kit.
Can I get a few suggestions from any Citrix shops out there, what are the pitfalls and can you patch one box and see the result or can you not observe the results unless all servers in the farm have been updated?