I purchased the Laser Ammo in early 2014 and just this week finally wore out the original battery that came with it. It has been used at least once a week in these two plus years and I think it has been a valuable in giving me practice time when a trip to the range is not possible. With this laser bullet my garage or upstairs storage room has served as a place to practice drawing and firing with or without using the sights. My P229 has double strike ability in the double action mode while other pistols require being cocked before firing. The cartridge will not eject when the slide is cycled as it does not have a groove for the ejector to engage, and I use a pencil to push the cartridge back to the ejection port to remove it. The cost of the cartridge is under $100 at Amazon and I have saved hundreds of dollars in ammo by using it. But more importantly it has made dry firing practice a lot more fun.