I'll have a look for it
DAN, PADI, Dive assure and Diver Security Insurance was reviewed I think. There weren't any main differences overall, just the smaller category differences: i.e when the insurance starts (when you get on the boat, dock, get in the water etc), when it ends, what other stuff is covered (i.e. accidents while monkeying around on the boat during the SI are not covered) etc, knocking your computer over the side of the boat not being covered....
It basically came down to what type of diver you are and the people you usually dive with.
It might be this one, but I remember much more detail & everything being summarized in a table:
www dot scuba diving dot com/training/basicskills/TN_basic_consumers_guide_to_dive_insurance