advice on purchase of hand held vid cam

I am contemplating adding a video camera to my inventory...some things are a given, digital, of course, HD, yes, handheld, yes so I can travel with it,( I do a couple of trips down to the tropics each year) and I prefer newer technology, mostly because I seem to always buy " last years hot thing" ...I want something I can use topside, but also something that I can take under...I have been advised that the Sony HC 9 -will probably satisfy my needs..over the Sony SR 12...because I can use miniDV, and not have to lug my laptop around with me...I also understand that LUX ( a new term for me) can be an issue, and that a handheld is going to have certain limitations in a darker environment ( like the kelp forest here in Southern California, where I live and dive frequently).. but that getting a camera that deals better in low light involves getting a much larger ( and probably more than my budget will allow) camera...I just wanted to get a little further input before I finalized the deal..this is purely for consumer use, nothing fancy, but I want to still be happy with my purchase a year or two from now....as always, thanks to the community for your input...J.K.Jetton