recommendations for centrally managed corporate antivirus solution

[illuminaeti () gmail com]

Hi list

On the different networks I manage, I've been using Symantec corporate since version 7. I've never had any major issues 
with it until now. 

Version 11, now called "Symantec endpoint Protection" requires IIS and either MS SQL or the symantec embedded database. 
I installed a copy on a test server and it just about crippled it. Network access from clients was incredibly slow and 
processor use was hitting %100. I've heard the same comments from a collegue who installed it on a new server at the 
customer's request. The file server was virtually unusable even before the client was installed on the workstation. 
Also the new GUI is just plain awful. 

 I don't have the time or resources to tweak settings to get better performance out of the AV.  
 I've heard good things about NOD32, Sophos and Kaspersky.  I've started looking around and of course, every website I 
visit tells me the software they sell is the best in the universe. 

So, looking for real answers from real users, I thought I'd ask you all about your experience, positive or negative, 
with various corporate antivirus software.

Thanks in advance.