Do some searches on the gun forums, including this one and you'll get some good info.
The bottom line on "Less lethal" ammo is simply this: Use by citizens for home defense is both suicidal and stupid.
First, less lethal is for use ONLY by the police in situations were they are fully covered and backed up by other police armed with LETHAL ammo, and in situations where they think they can take the risk.
Less lethal ammo FAILS in many or even most cases.
Second, is the legal situation.
Bottom line, the law is very definite: If you fire a gun at someone, it doesn't matter if the load is buckshot or cotton balls.
You have fired a deadly weapon at a human. If the situation is serious enough to warrant firing a weapon, it doesn't matter if that person lives or dies, legally.
What all this comes down to is this.
1. Using "less lethal" ammo is suicidally dangerous for an home owner, due to the high possibility it will fail to stop or deter the bad guy.
2. Firing less lethal ammo at a person IS deadly force according to the law. Attempting to "deter" someone in a situation where you don't think lethal ammo is warranted will see YOU charged with felony crimes.
3. NEVER, EVER, NEVER base or plan your defense on being able to fire more then ONE shot.
In the "real world" you're lucky to get one shot, and that shot had better be an effective one.
Imagine a situation where you've just fired a less lethal round in your living room at 3:00 am, and it FAILS.
Bad things happen in the real world. Your gun jams, the next round fails to fire, the bad guy gets off a lucky shot, you stumble, whatever.
You now have an ANGRY armed intruder in your face, and HE isn't going to be firing a less lethal round to give YOU a break.
To quote famous Border Patrolman Bill Jordon: "Like being just a LITTLE pregnant, there's no such thing as shooting a human being "just a little". If you have to shoot someone, shoot them GOOD".
Less lethal ammo is NOT for use by citizens who aren't backed up by other people with lethal ammo covering them.
Less lethal is is ONLY "less" lethal. It can and will kill, and is legally considered to be no different than a Magnum load of buckshot.
Trying to NOT shoot someone by shooting them with less lethal ammo is legally wrong and can get you charged and sued.
Planning on firing a less lethal round, THEN planning on being able to fire lethal rounds if the first fails, is suicidally foolish.
Trying to "give a break" to a person insane enough or violent enough to invade your very HOME is itself insane.
Anyone invading your home or confronting a person armed with a shotgun is NOT normal.
Is it your intention to put your life and the lives of your family in the hands of an insane, abnormal person?