First I'm gonna tell you what you seem to want to hear. If its not leaking now leave it alone. Now I'm gonna tell you what I would do if it were my car I would get the car flushed of that stop leak crap and put in a new freeze out plug, especially if I lived in Florida where it gets hotter than hell in the summer and don't forget to use fresh MB antifreeze. It will be cheaper in the long run believe me.