These islands are foreign countries and most are not suitable for going off alone. However for most tourism is the only game in town and they try to protect their good standing with tourists and cruise ship passengers.
Tips on going it alone: know where you are--you can take a cab in Cozumel or Grand Cayman in relative safety, whereas I would never try this on Jamaica or Belize.
A slick website does not indicate these people are professional. Anyone can post great pictures and "reviews". A website like this one with experienced cruisers can be a wealth of information on vendors they have confidence in. After frequenting this site for several years I often feel I am getting a referral from a trusted friend.
Having had an extremely bad experience with a ship sponsored tour--far less safe than any I have done on my own--I do not have a problem looking around for other vendors. For instance Shoretrips.com is bonded, insured, USA based, and I have never had a bad experience with them--but there is no real savings.
It is all a matter of what your comfort zone is. I think price can be an indicator also--if it is just too good of a deal be very suspicious about what will be "included"!
RCCL Nordic Empress 1993
RCCL Nordic Prince 1994
RCCL Explorer 2003, 2005
RCCL Navigator, 2004, 2007
RCCL Mariner 2006
RCCL Liberty 2008
RCCL Adventure 2009
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