My situation is slightly different, in that I have my own business and other "work-ish" activities I'm involved in, but also have a strictly 8-5 "job." I have the issue of not being able to have one system due to IT constraints at my job. I have no input (other than the very occasional idea that comes to me after hours, which I just email to my work email) related to work unless I'm at work. I don't even need context lists for my next actions at work. Just one action list, a waiting for, someday/maybe and a project list.
I have my "everything else BUT my job" lists accessible on my iPhone, and I always have capture tools for when I have "personal" ideas at work (or anywhere else). I have NO problem having these two systems, but I will admit that I'm probably in the minority as far as having such a dividing line between my work and personal life.