It largely depends if you are buying for now, or the future. If you want a device that you can configure from a simple GUI right now, but that will do a fraction of what a pfSense box does, then buy EdgeMax.
The USG is clearly the runt of the Unifi litter, and clearly the controller isn’t finished with regard to features like multi-WAN, some aspects of VPN and port mapping. Even some DHCP features are still absent. The rate at which they are adding features suggests that that is where the long-term smart money would go. That said, most of the ‘advanced features’ in a Unifi are still a Beta. Even in the LTS releases far too many features are still marked as Beta.
As for processing power, the USG-3P will handle any UK FTTC connection, with all features enabled. For FTTP or a Virgin Fibre connection, you probably want the USG-4P.
It’s a myth that the USG isn’t ‘powerful’. It will handle a full Gigabit connection if you just want simple routing. The ‘advantage’ of EdgeMax is that it has a more straightforward GUI model. It only has to handle routing and simple firewall rules (because it’s just a router). Anything Unifi also has to handle all the complexities of the switches, access points, lights and whatever else they UBNT skunkworks can come up with under the Unifi banner. So the USG will beat the EdgeRouter Lite for processing power.
Right now, you may well be better off sticking with pfSense if you know that system. Or a Mikrotik hAP or wAP if you want something new and shiny.
