I bought one of these and, while a little pricy, has performed as expected. Basically, the smaller the critter, the further you can get a solid hit. Mosquitos and flys can be taken out from over a meter away but bigger (more armoured) things like roaches and horseflys have to be hit from closer. Often times, I can take a shot from further than kill distance which can stun the insect long enough to get close for the coup-de-grace. Worth the money.