Please remember than DAN provides more than just insurance; they also talk to your doctors/medics and act as your advocate.
If you have a DCS problem, DAN absolutely wins on balance.
If you are only talking travel insurance, then the game is wide-open to much more thatn DAN and Dive Assure.
DAN did not act as my advocate. I had a DCS incident in Cozumel, several years ago. My doctor (Dr Piccolo) recommended an 8th chamber treatment. His wife, Heidi (who does his administrative work) told me that DAN wouldn't pay for it because they have a strict limit on the number of chamber treatments, regardless of medical necessity. Sure enough, DAN denied my claim for the last treatment.