eTrust anti-virus

We are currently very unhappy with Sophos anti-virus in our school due to the major resource sucking that occurs whenever it updates and does a scan. On the older machines in the school we end up with an hour over lunchtime when no-one can do any work on their computer as it is so unresponsive and on our new machines (about 2 months old) the machines become pretty sluggish.

Now, my question is regarding etrust antivirus. Our LEA provides it for free to any school that wants it and I am considering testing it out to see if it is any good.

Does anyone here have any experience of it?

No-one?

I saw a shortcut to eTrust AV on a presenter's machine at the MS TechNet Roadshow on Tuesday. I believe it is their enterprise choice for AV...