Laws differ from state to state.  The top enforcement officers on my lake in NH for Marine Patrol and Fish and Game were the same mustang as mine and said an additional is not required in NH if I am not wearing one. They both also told be that even if it was, the fact that it is on the back of my seat would be good enough.

Truth be told, we all have the orange cheapo.  It makes for a good protector for my back-up prop ?

The varying rules bothered me, so I just called the head of NH Marine Patrol.  He said it is one of the most misunderstood issue he sees and admits many of his subordinates don't understand it.  He said it is because it has changes 3 times over the last couple years.

The bottom line is that they do not distinguish between pull cord and self inflating so they consider  all to be pull cord, thus making it legal if worn.  It does not count if not worn since a pull cord won't float if not activated.  Lessen learned!