What are the pros and cons of deregulating health insurance so consumers can buy across state lines?

I know the obvious pro would be to create competition and hopefully lower costs, but would there be any other benefits? Also, are there any little-known risks you're aware of?
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Not so obviously. The real pro, is more competition. But there are some major issues dealing with it, because each state requires different things of insurance companies. Some states require coverage for infertility treatment, which drives up rates. Some require that an insurance company CANNOT turn down an application, they HAVE to give health insurance to EVERYONE who asks for it - which triples rates. I think the result of allowing policies to be sold across state lines, will result in an INCREASE of rates for people currently in more restrictive states, and a DECREASE in health insurers willing to write new policies. There is no federal insurance oversight - each state regulates policies sold in that state. So, to do health insurance across state lines, will require a new federal oversight department. How will you fund that? Bottom line, I can't figure out how it could possibly cost less.
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