What I am looking for in this thread is for those who work in the field to share their experiences with MA and their job. Surprisingly, most police officers I know don't do any type of MA and it's hard to get opinions on what is effective and what isn't. Most guys who are concerned about this just get bigger thinking it will resolve most issues.
I've ruled out a few gyms in my area due to some of the associations they have with persons of questionable character. There is an RMA gym near me that teaches escrima, BJJ, submission wrestling, some boxing, kickboxing, etc. As mentioned above, I've dabbled in most of these and I've implemented a few of the techniques with varying degrees of success.
For example, I've found BJJ really taught me how to control someone on the ground. No shit, right? Once you flatten their hips they become much easier to control. Many people don't know this. I see people grabbing arms and legs only to see the guy get back on his knees and stand up.
Wrestling seems like it would be great but it requires you to have a lot of bodily contact with the other person who may be filthy or have contagious diseases.
Boxing is good for avoiding strikes and knowing when someone is about to sucker punch you. MT teaches the clinch which is useful for obvious reasons.
This is the kind of stuff I was hoping to share.