As far as I can tell it's as follows (I called thier sales number and asked.)
If you use the free version for home use, you can have ONLY 3 NIC's in your firewall. You can only have 10 clients behind this firewall. You don't get antivirus, or URL filtering, unless you pay extra for them. The AV is $50 for personal and $295 starting for office, and I'm not sure how much the URL filtering is for personal, but it's $275 for office starting price. Please don't quote me on these prices, I'm just going off the PDF they sent me. I'm not an astaro rep, so my word is not official on this... ;-)
