Harder job than who? I don't think that they work harder than any of the rest of us (they have a pretty easy job when compared to others IMO, much easier) ... and OSHA stats show that they are pretty safe as far as employees go...safer than my group and likely safer than most on the board.
Not to many stories of OCers going nuts ... OCers are, as you said, very conservative of pulling their guns out.
Cops? They pull their guns out many more times unnecessarily than regular citizens do. I've had about 20% of cops pull guns out during traffic stops. They appear to be rather afraid in their own job.