Pros: -fairly easy to setup with 20 VPN users
-reasonable price
-great feature set
-runs quiet (unlike Cisco security appliances)
-fast VPN throughput even when IDP is enabled
*annual subscription is reasonably priced

Cons: -manual was not the easiest to navigate
-annual pay subscription required for security updates*

Other Thoughts: I would recommend this VPN security appliance from Zyxel for small business use. I found it to be FAR superior to "comparable" Cisco products I have used in the past.

Pros: 1. Fast compared to other devices in the same price range.
2. Very detailed configuration options. Policies and be easily applied to arbitrary combinations of machines on the network.
3. L2TP for native VPN support for iOS/OS X.
4. Lightweight DNS server builtin for those with a small number of devices on the local network with a hardcoded name and IP address.
5. Fan speed control. Fan will stop if the device is not busy.
6. Outstanding online documentation available for download from the manufacture web site.
7 Even though the complexity of the device is high, most of the features actually work as advertised or the way you would expect them to work.

Cons: 1. The actual AV throughput is nowhere near the advertised throughput.
2. The learning curve is a bit steep due to the complexity of configuration.

Other Thoughts: I'm a power home user that bought this to protect the local network and for occasional connecting to home via VPN through a smart phone or laptop. This device was purchased to replace a 2 year old UTM of a different brand. In general I'm very happy with the new device.

I have 100mb/s cable at home and I bought a higher end device since very few of these UTM devices can do anything close to full network speed. The USG110 is very fast in general to the point that I can saturate the cable connection with all the protections turned on including content filtering, but with anti-virus turned off. With AV turned on, the device typically gets about 30-50mb/s which is nowhere near the advertised speed of 250mb/s. This is a bit disconcerting, but the USG110 is still about 2 times faster then my previous UTM at a fraction of the cost. It's also very easy to exempt some machines from AV protection or disable AV when occasionally downloading large files.

The fan speed control is a huge plus. As mentioned, the device will put the fan into low speed or even stop it if the traffic is low. This is great for the home or small business environment as excess noise can be a real problem.

Finally, I would like to mention that like most UTMs content filtering can remove many of the annoying ads from web pages that slow things down.