Here is some links regarding penetration of regular ammo and a 9mm glaser rounds. A 9mm glaser round went thru 6 boards of sheetrock. Isn't failure to penetrate walls the reason why I would spend so much money on glasers?? To be fair even the Glaser website admits that any projectile will penetrate sheetrock, glaser are meant to stop hitting something more solid like a wood stud or a door. Second link same website, water jug test, glaser round goes thru some clothing and enters a 1 water jug, and tears it apart, but fails to exit. However the Third link mentions various bullet wounds cause by glaser rounds. Nasty, Nasty wounds, If and this is a big IF, the bullet penetrates. In some circumstances Glasers were more lethal than a regular round, and in some less lethal but a wound regardless. I rather take a FMJ bullet in the stomach than a Glaser. The problem with Glasers in pocket calibers I think are bone penetration with a bullet hitting shoulders or even the skull. In a hostage situation I rather have a HP .380 instead of a glaser .380 and that is knowing that if the glaser was to pentrate the skull , it would do significantly more damage to the brain than a HP, The Glaser might just fracture the guys skull, give him a gaping, bloody wound and put him in a world of hurt, but not kill him. I think glasers are a good thing, just understand, as with every bullet, they have their good points and their bad. If you know what they are you can use that bullet effectively.