I've done a lot since the last update. The motors are working well, as are all the ESCs, but I have been tackling a noise problem with signal crosstalk. Through lots of troubleshooting and frustration, I swapped out the old wires for a color-coded twisted cable and added a 0.1uf capacitor for each ESC. This got rid of all the noise but several motors weren't responding. After checking all my connections, I re-soldered everything and found that the PCB is defective and one of the traces was ruined, leading to no signal contact. The new PCB should be here any day now, its been about two and a half weeks.
Speaking of which, the Spakfun PCB forum was extremely helpful for finalizing my design, I'll list the changes when they come in. The fresh Digikey and Sparkfun orders came in, this time with the single power regulator, a magnetometer, and GPS with antenna. Version 2 is going to be so much better, lighter, smaller, and more awesome than the first one with completely integrated control and inertial measurements on one thin, small board.
And now for the bad: Waiting for shipping is awful, as usual, and HobbyKing has been out of stock on the 0.3g ESCs for over 3 months now! I can't order replacement propellers either, since I broke one of those as well. Gahh!