I have become an advocate for using shot timers for defensive shooting training. In a real world shoot, I'm led to understand the first person to put effective shots on target has the greatest chance of surviving. Mindset, decision making skills, reaction time, accuracy, then speed. Shot timers can help with both speed and accuracy. One of the keys to the speed/accuracy component is rhythm. If you're familiar with the term 'riflemans cadence', you know what I'm referring to. Most people shoot more accurately with a rhythm. A shot timer can give you a precise snapshot of how long it takes to draw and fire, split times between shots, magazine reload times, and so forth. For those that believe carrying an empty chamber adds only a nominal amount of time to their first shot - a shot timer can give them an accurate number to confirm or disprove. It encourages training! In short, if you carry for own a gun for personal protection, consider incorporating a shot timer as a useful asset.