Has Ubiquiti started shipping the toolchain necessary to build their Linux, or are they still violating the GPL?

When last I checked, you could not compile your own kernel for Ubiquiti devices and get something that worked the same way as before -- the switch ports, IIRC, and probably other stuff.

My firewall runs actual Debian Stable, gets updates to everything including the kernel, and happily handles the gigabit that VZ claims to be delivering to my house. (Actual speeds tested vary from 700-950Mb/s.)