It is really no hassle going to Trunk Bay on your own. Yes, you did pay more for the ship's tour and if you will be happy spending more time getting to the beach and back then you will spend on the beach then the ship's tour is a good choice. We prefer to go on our own because we like to have some time to relax and enjoy the beach and then we leave when we are ready to leave not when they tell us we have to. Last time we were there we spent a couple of hours at Trunk and then grabbed a taxi and went to Cinnamon Bay for a couple more hours. The ship tours came and left Trunk Bay while we were there and we had beautiful Cinnamon Bay all to ourselves. It was an amazing day. I have pictures of both beaches in the Explorer albums at http://community.webshots.com/user/jean_lynd
if you would like to see what it is like to go there on your own. Happy planning!