According to Florida law, you can use deadly force to prevent the imminent commission of a forcible felony.
Once somebody unlawfully enters your dwelling/residence (or an occupied vehicle), you can pretty much pick your "forcible felony" as justification.
The obvious grey-area is when somebody runs away --- you're protected by SYG in your kitchen, and probably your foyer, and maybe your front-porch (maybe). But if somebody is running away, and they're 45 feet down the sidewalk, it's difficult to pretend they're an imminent threat to your person/property.
776.08 Forcible felony.—“Forcible felony” means treason; murder; manslaughter; sexual battery; carjacking; home-invasion robbery; robbery; burglary; arson; kidnapping; aggravated assault; aggravated battery; aggravated stalking; aircraft piracy; unlawful throwing, placing, or discharging of a destructive device or bomb; and any other felony which involves the use or threat of physical force or violence against any individual.
http://www.leg.state.fl.us/statutes/index.cfm?App_mode=Display_Statute&URL=0700-0799/0776/0776.html