.22 lr instead everyday. Ammo is much more available, and far cheaper. .25 is pricey and quite expensive to shoot while at the same time carrying less power than a good .22. It’s ONLY advantage is that it’s centerfire and a bit more reliable ignition wise. It you MUST use a mouse gun, then .22 with quality ammo. For defense, get a more powerful round. 9 mm ammo is typically a LOT cheaper than .25, is a LOT more powerful, and is available in a wide variety of handguns in sizes from small to full size service pieces.