You know, we were discussing a complete computer for one supper price, the HP ML10 and it costs $199. You can't beat this deal. The one pitfall is the video output is a Display Port connection which means that if you do not have this type of connection, you would need to buy an adapter which would cost you anywhere from $6 to $20 depending on where you buy one. I'm not sure if the ML10 has the adapter so you could either buy one up front or wait to see if it comes with one. You would also need to purchase a single or dual port NIC card so this would be an additional cost. But in total you would have a functional system for less money than the Supermicro one you have listed now. Also, I'm not trying to talk you out of the supermicro system, it looks pretty nice, I'm only offering up options since you asked for them.
Also, an option to using a different piece of software is Sophos. I'll be honest, it's a pain to setup if you want all the bells and whistles but if you want the basics, it's not terrible. It's also free and patern updates are checked as frequently as every 15 minutes. It's also a set and forget if you like. It also has built in Endpoint protection meaning that it can cover your computers and technically you don't need a firewall nor antivirus software on your computer, but I still run paid software on my computers. Again, just another option and I'm attaching a screen shot, you will note that I do not use all the features.
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