I have a TG-4 and a coolpix aw120. They are both good cameras. The TG-4 is more flexible (gives you more control over settings) but more complicated to use. The coolpix is more automatic and simpler to use. I find that the coolpix has more of a tendency for the lens to fog
when immersed in cool water. So much so that I actually run my genset and air conditioner and blow dehumidified air into it for about 2 minutes before I take it in the water. The instructions even say to only open the cover in a low humidity environment
. Where do you find one of those on a cruising boat? I have also found that storing it in a sealed plastic container with desiccant helps. If you purchase
an external battery charger
you can minimize the amount of time the cover needs to be open. Why do I go through all this trouble for the Nikon? It's just easier to use underwater. I do a lot of macro photography
and it is much easier to do it with the Nikon than fumbling with all the settings on the TG-4. Things you want to take pictures of underwater often don't wait around for you to fumble through a bunch of setting options. Also The TG-4 has a round central lens that looks like a big eye, while the Nikon has a square lens up in the corner. I find that smaller fish
tend to freak out and leave when you point the TG-4 at them but not so with the Nikon. I guess in the ocean when something with a big eye starts focusing on you it is not a good thing. Another thing that affects my photography
that may not be an issue for you is that the corner mounted lens of the Nikon allows me to take macro photos and videos of creatures in small holes because I only have to get the corner of the camera in the hole to do so, where I could not possibly get the center mounted lens of the TG-4 anywhere near the hole.
model of the Nikon is the AW130 which seems to be an AW120 with a deeper depth
rating. Both Cameras seem to meet your basic needs. If you just want a simple point and shoot I recommend the Nikon. If you want to play with a lot of optional settings go for the TG-4.