I was hired to be a part-time security officer, but I worked full time hours. Not only did I work full time hours, but I also worked all 3 shifts...including all 3 in one week! No benefits, no raises, only 3 sets of uniforms, when they called you to come in, you'd better show up or get written up.
For the type of work I did, I had to have a security clearance, I was basically a glorified receptionist.
As for coworkers, some were great. Others would pay you on your back to your face, then slap you in the face behind your back, just to try to move up in the company...which was extremely limited. I submitted ideas to the management, they were approved, but some of the 'older' officers would sabotage them. Ideas that were designed to make our job a little easier, were trashed...literally. And if you have more, or higher levels of, security experience, the opposition will do anything to discredit you and that experience.
Companies like Allied-Barton are the definition of 'revolving door workplaces', because people never stay long.
Cons
Hard to maintain a work-life balance