Traveling there from Singapore to Tonga is a bit of a trek. Because we had to fly on certain dates our route was Singapore - Sydney - Auckland - Tonga - Vava'u. Timings were OK though, max overlay time was about 2-3h at each stop.
We didn't have a chance to visit any other Islands unfortunately.
In the end I had decided for a smallHD dp4 but it's good to know there's a 7" option out there now as well with actual sdi support. If I end up wanting to upgrade to a 7" the dive & see monitor is definitely on my list.
Thani, thanks for the advice! Yeah the green peaking definitely helps but I don't find the auto focus to be very useful though since it tends to be very slow on the bmcc.
For my style of diving & shooting I find having an external monitor helps a lot, since I can keep the camera slightly below me with the external monitor angled for better viewing. At the same time I have a better overview of my distance to subjects - (or rocks) -- before that I have managed to bump my domeport (and scratch it :/) more than once when using the bmccs built in monitor.