Bought one out of impulse for my girlfriend to take on our dives. They have a new SP8 that has a separate housing you can buy which is only like $70 that allows you to reach ~130.
I originally tested it on the Hilo side of the Big Island just as the sun was setting. In from what I can tell its wasn't going to be the best outfit for low light environments. The visibility off 4 mile that day wasn't that well so I wanted to really give it a chance during the day in some clear water. Today in Kona it was ~9am and the sun was almost perfect. Water was pretty clear in the shallows on the south side of Kahalu'u. I kept to the underwater modes they have setup in the camera, Macro, Sport and Normal. I liked the way some of the photos turned out. Not bad at all for a handheld in my opinion. My only complaint is the speed in which it takes the photo. The time it takes to set the focus and actually open the shutter is significant enough to where I missed a couple good shots. I am patient and so is my girlfriend so I think this camera will work for now. She gets this one, I get the 5D Mark II.
Once we take it on a dive with us I will post up photos from different depths if visibility permits.
Here are a couple samples I took today in Kona.
Resized 1600x1200 (PM me if you would like a full resolution photo)
10-12' distance Photo (Underwater Sport mode)
Underwater Macro Mode (Not too bad)
Underwater Sport Mode
Cropped 5-6' distance photo
I live on the islands....it says you make these in Honolulu, feel free to send me samples, I can test them, post reviews and mail it back.