UTM w/ QoS that works well?

I currently use DD-WRT as a router for my 12/2 connection. The one connection is used for both my general Internet browsing/traffic, and VOIP for my small business (FreePBX connected to Callcentric). The QoS on the DD-WRT handles traffic superbly.

But a friend runs a business where he has to store social security numbers and all sorts of data that he needs to protect. So he is rightly concerned about trusting security to DD-WRT.

Right now he uses an Astaro UTM. The interface for Astaro is awful. And I cannot find any good documentation that tells me how to handle both inbound and outbound QoS for VOIP.

I’ve looked at Untangle, and the interface is much better.

But there is also Smoothwall, Clearos, etc.

Does anyone have any experience with these UTM (Unified Threat Managers) specifically when it comes to QoS and ease of setup? I’m interested in trying something but I don’t want to waste time on units that don’t do a good job at QoS.