How are you liking Untangle now that you've been running it for some time?
I like it a lot. the UI is somewhat pedestrian and once you get used to the traffic flow it gets easier to track down problems. For instance, say you have an app or a service getting blocked... it could be NAT or your port forwarding rules, the Firewall, the Ad Blocker, Application Control, SSL Inspector, or the Web Filter. That's a lot to take in.
But it's done everything I needed, which I cannot say for Sophos UTM or pfSense or OPNsense. The only bummer, and this has nothing to do with Untangle per se, is that SSL packet inspection is becoming more useless every day. As more and more apps and services start verifying certificates internally, the exceptions needed "to keep things running" just isn't worth it at times.
Performance-wise, I'm running it on an old Dell box: Intel PentiumD 2.80GHz, w/3GB RAM, 120GB SSD, and dual Gbit NICs. Memory usage is steady at 50-60% and the CPU is rarely breathing heavy at all.
My only real concern is speed sometimes but I'm not sure if it's Untangle, the destination sites, Comcast, or GoogleDNS resolution or... ? Sometimes I'm hitting a site that's super slow, or it takes a while to resolve, then I run a SpeedTest and it's ripping at 175 Mbps. I feel like Comcast is prioritizing speedtest.net so people get good speed results while throttling other traffic, but I have no data to back that claim up.
I just switched over to CloudFlare (1.1.1.1) for DNS so we'll see how that goes. AT&T ran fiber in my neighborhood in the fall so I'm gonna give that a whirl when they turn it up.