I am an amateur freediver, I never got deeper than about 30 feet - and I don't think I ever will. I plan a vacation trip and chances are I will be able to dive on reefs. I am looking for some cheap (or at least not too expensive) underwater camera, that will also serve as a backup 'idiot' to my DSLR. I know about Canon Powershot D10 - any other similar (better/cheaper) cameras of the same type?