While taking his Tx LTC course my brother fell in love with the holster our instructor was using for demonstration purposes. He liked it so much, he bought one. Its one of those outside the waistband plastic holsters with the pushbutton release on the side.
While waiting for it to arrive he read up on it and found that more people have an accidental discharge while drawing from this kind of holster than with any other type. Evidently folks push the release button with their trigger finger, but forget to release their inward finger pressure as they draw the handgun, resulting in the finger pulling the trigger as it clears the holster.
To prevent making this kind of potentially deadly mistake, the first thing my brother did, before ever carrying with it out of the house, was practice drawing his unloaded weapon about a hundred times a day for two or three days, to condition himself on the proper and safe way to push the release button and draw the handgun without allowing his trigger finger to touch it on the way out. He was terrified, rightly so, that he would have a careless accidental discharge out in public if he was ever in a "draw your gun" type of situation.
In my opinion, this type of preparation should be done with any handgun and any holster you plan to carry.