Having decided that I didn't want to be wielding a camera underwater, I found that the dive centre in Barbados are happy to get a guide to take video/pictures but have no cameras. Googling around, I came across the Veho Muvi K series that has better reviews than GoPro and, with signing up for a 30-day Amazon Prime trial came out under £170 including waterproof case to 100m, lots of fixings, 16Gb card, spare battery and a nice hard case to keep it all in. I can't believe how tiny it is and most of that is battery. I'll leave it to the expert for the holiday and then take it from there. I've never seen myself diving, my view that my trim is good may take a bit of a battering. Can't wait to get it wet in nice warm water.