Stand your Ground laws need to be appended a bit. Here's why. Suppose you get in a random fight at a bar. Most bar fights end pretty quickly when the two realize that getting punched sucks, or when they get ejected. However, with Stand your Ground laws the way they are, you have no duty to retreat and can simply pull out your gun and shoot them as soon as they get the upper hand over you, saying that you fear for your life. Similarly, when you pull your gun, they'll pull their gun, saying they fear for their life. So what you have is both combatants standing their ground and the fight won't end until someone (or both of them) is dead.
It also leads to situations where you could go pick a fight with someone and then shoot them before they even get to you because you feared for your life because you thought they had a weapon.
There's going to be a lot of people using Stand your Ground laws as an excuse to escalate a run of the mill fight into a deadly situation that wouldn't otherwise have turned deadly. Some things might be justified, like if someone is car jacking you or trying to force their way into your home, but other things wouldn't..like someone catching you in bed with their wife and ending up dead because you feared for your life and had no duty to retreat from their home.