I did my homework a few years back and came up with Trend Micro, and have been selling it since. It certainly works well, and about the only thing you need to do with the new versions is tell the server not to do the scanning so the user response time to file-open isn't so slow. (E.G. set it back to the old behavior.)

I recently picked up a customer who didn't know which way to go, and they had Network AVG installed. It showed they had a lot of viruses. When I started checking them out, I traced the most of them down to be false positives that was set off by their Zebra bar code printer driver software. I've had a false positive once with WorryFree also with VISI CAD software. VISI since changed their software due to the ubiquity of WorryFree. A couple of their workstation infections were real. One it showed 95 infections when there were in fact two. I'm not accustomed to misreporting from WorryFree. The other one shows 11, but it's a laptop and not currently available for me to look at so I can't say what the situation is there yet.

The customer fully expects me to remove AVG and install WorryFree since their contract is up this month, and WorryFree certainly doesn't cost more. However, I'm not where they think I am. I have spent little time working with AVG. These are my impressions thus far:
1. AVG has a heavy footprint on workstation memory compared to WorryFree.
2. AVG has a lot of noisy options that are not needed that WorryFree just does.
3. The AVG interface is waaaaaaay more efficient than WorryFree. With AVG you have an Explorer type tree on the left to drill down to anything you like. With WorryFree you can't even drill down on a workstation that reports viruses and find out what they are. You need to set up a report with date ranges, and wait for it to go through it's database. If your dates are wrong, and you do it again. Sure, you can schedule reports, and most of the time they will have nothing. That's like checking the door once a day to see if anybody is there instead of having a door bell.
4. To get notifications and monitoring with WorryFree, you need to use Trend's, and when you get a warning from their site, you need to figure out which server it is. I hate it.

Questions I have from both Trend and AVG users:
1. What is your experience with AVG catching viruses compared to Trend if you know? I know they likely miss different ones, but overall?
2. Is it more common for AVG to get false positives? I know with WorryFree I've only had one occurrence ever across all of our customers, but I have no context to work from to determine if this is more common with AVG. Reporting 95 infections when there are two also doesn't inspire confidence.
3. WorryFree doesn't tax the workstation to any noticeable degree, even during a full scan while the user is working. If it weren't for the animated icon, he wouldn't know it was in a full scan. I don't have any experience with AVG in that regard.
4. At first glance it APPEARS you can control the workstations the same as you can with WorryFree, but I don't know if there is anything lacking there or not.
5. I have no idea what method(s) AVG uses to roll the workstation software and updates to work stations.

If there is someone here that can clarify some of the significant differences, that would be helpful.

Thanks tons!