We use a Forespar man overboard pole as a starting pin. They float jauntily upright and are tall, thereby making an ideal pin...
until they sink! We lost one earlier this year. We chalked that loss to overloading the tackle with chain so that it doesn't foul boats. The next one began sinking too, even though it had no chain. We rescued it with a foot to spare.
The reason it is sinking is that there is a tiny drilled hole in the top of the orange flotation. The pole bobs up and down, sucking in a little water each time... then glug, glug, glug. The pole is gone. I've contacted Forespar and their rep is going to look at it when he gets back from the Bermuda Race.
I suggest everyone double check their own gear to make sure it doesn't have a similar problem.