If you are going to be a wafu and join a ships flight you may be asked to do the dunker. Most members of the flight ride in the helicopter at some stage and as it frequently over water it is worth doing the dunker. I was on Manchester flight in the early 80s and out flight commander requested members of the flight to do it. By now it may be mandatory. It's no big deal and there is no danger,. Do it and enjoy it :thumright:
I wanted a go at the submarine escape tank when I did my dunker (the dunker was on top of the tank) unfortunately it was restricted to submariners.