I would recommend a thumb break holster for you because you just can't pick and choose when, where, or how a confontation will happen. If you end up on the ground your carry weapon may or may not come out prior to getting to it. But why take a chance? Here in Oregon a man went to a movie theater, and somehow someway his ccw came out of the holster. Movie gets over, and he leaves his weapon sitting on the seat as he leaves.
Theater staff finds it and calls the police. News media gets a hold of the story and with all the school and mall shootings, this now becomes a major event. The event ends with a resident coming forward a day or two later, and saying it slipped out of the holster unintentional and I'm sorry. He get's charged by the county DA, for creating a hazard and another misdeameanor. Also, since a crime was committed, the county sheriff may revoke his concealed carry license.
Do you hunt, hike, fish or spend time in the woods. Sometimes footing could be an issue and down you go. One of our LEO's was fishing, and was netting his catch and somehow his unsecured off duty came out and went into the drink. Fortunately the water was shallow enough and he was able to retrieve his off-duty weapon. My feelings are "why take a chance" and releasing a thumbreak snap is so easy when drawing.
My opinion, others may vary.................