if you want to see very similar functionality- state based search of health insurance based on individual profiles, just surf
www.ehealthinsurance.com
i've stepped-through the cal state exchange, and i've bought at the site above, they're similar. the gov site does more by validitating yrou identity via your credit report( calling a 3rd party is no biggie to code) and also determining your eligibility based on the income you input, again, no biggie, many gov sites do that already.
wehi allow focused geo-based searches and also doctor's searches, i.e, I can input my doctor's name and see all of the plans available he accepts.
i doubt ehi paid 10s of millions for their operation