I want to get a shot timer to help me train for IDPA. Ideally, I would like something that I can use at a public indoor range. This means that the timer will either need to have a way of filtering out the bangs that are not mine and the echos, or use an alternative means of sensing a shot (e.g. wrist worn timer with an accelerometer). I see that there are smart phone apps that claim to provide adequate measurements for training purposes. Then there are the dedicated shot timer devices, most of which use a mic to listen for shots. However, I know of at least one timer that is worn on the wrist like a watch and uses an accelerometer to sense the shot. What timers have you used? What timers do you reccomend?