I don't know about "a sure ticket to..."
but in any marginal case where there are doubts about the necessity of having to use deadly force, and it's illegal to shoot somebody just for being a trespasser,
this kind of a sign could come back to bite you.
The law of self-defense requires that you have a certain MINDSET when you pull the trigger. This type of sign CAN BE SAID TO indicate a bloodthirsty mindset and a willingness to use force illegally when it is not necessary.
Then, the only real question is does your putting up that sign at some point in the past accurately reflect your mindset weeks or months or years later under different circumstances when you actually confronted an intruder?
