The ERL family is pretty bad as a router, in my experience. There is a longstanding firmware issue that introduces packet loss for routed packets (it doesn't multiplex across the dual cores correctly, which leads to out of order packets). If you really want to use Ubiquiti, I would suggest using an ER-X which is cheaper, doesn't have this problem, and is quadcore.
The best option in my opinion is something Intel based running a well known Linux distro with automated security updates that is fully in your control. Shorewall can do everything needed for a home router. This option is a lot more expensive though.
The best option in my opinion is something Intel based running a well known Linux distro with automated security updates that is fully in your control. Shorewall can do everything needed for a home router. This option is a lot more expensive though.