Well every product has its downsides, in pfsense many wish there was good reporting but pfsense never got it yet, UT webfilter is great and it protects your devices against malware that are also using https and you get elerts wich device was blocked from malware, with squid and clam you have to use man in the middle to scan ssl, the bandwidth control is farrr better then traffic shaping also thanks to layer 7 you can prioritize based on apps not just ports and ip example torrent is always identified and put at low, in traffic shaping I always got torrent aat medium as it never got the p2p q, in 13.0 UT is getting fq_codel (also in free version) so if you like UT reporting I do not see any reason not to use it as edge firewall
I certainly agree that Untangle is great in reporting and that's why I use it behind my pfSense firewall in bridge mode!
Re the SSL filtering I am not sure how this works without doing MITM? It's common for a transparent proxy that wants to do SSL filtering you need MITM. Only if the proxy is a non-transparent proxy it can be done without but then it can be bypassed if you don't lock down your FW.
Anyway the main three reasons why I still use pfSense as my edge firewall and not Untangle are:
1) pfSense has a real firewall rules configuration section. Untangle's has filter rules but it's a bit confusing.
2) pfSense supports IPv6 through out the product compared to Untangle just passes IPv6 traffic through.
3) pfSense has unbound DNS to setup a real DNS severs instead of just the a forwarding DNS server.
Again that's only my individual view and hence I am running pfSense and Untangle to get best of both products.