For anyone else running into this problem, I was using this on an Ubuntu 14.04 system (stock cp210x driver). The serial port was flaky, meaning I would get part of the kernel log, then the serial messages would stop. It might or might not come back if I reset the Omega. I tried other USB ports and several different cables as well.

I changed to another machine and everything worked fine (meaning reliably). Morale of the story: if you're seeing weird USB/serial behavior, try using another PC.

Also, I tried connecting it through a USB hub and Linux didn't see the USB-serial anymore. If you're trying it in a hub and it's not working, try skipping the hub.

Hope that helps a random Internet passerby!