If you want to use it and it works sure. Comes down to preference and what you want to do with your computer.
Not sure what key you have for 10.8 and 10.7 as they did not have serial #'s for registration.
“If you are neutral in situations of injustice, you have chosen the side of the oppressor. If an elephant has its foot on the tail of a mouse and you say that you are neutral, the mouse will not appreciate your neutrality.” Bishop Desmond Tutu