I'm working with a new office that has a Watchguard XTM appliance. I'm not familiar with this device as I've mainly worked with Sonicwall devices. Is this a good or as good/better than the Sonicwall TZ205? Is it relatively easy to learn to use this device as I've worked with Sonicwall for years? The device is about 5 years old. If we keep it, what's the best way for me to learn to use it? The owner mentioned that his subscription to it expired a few years ago so I'm not sure if they're using it the way it should be used. Any pointers or recommendations are greatly appreciated! Thanks!