Don't fill out the on-line application! You will get a million phone calls as your phone number is distributed to dozens of partner companies, each of whom will try to call you endlessly, even after you buy a policy.
Call the 800 number at the top of the page. If you don't get a rep you like, hang up and call back. There are scads of them all selling the same thing. The person I used was very knowledgeable and forthcoming. Be prepared to invest time. At least an hour... to ask questions and then go through the screening process. Insurance was reasonably priced and went into effect the next day. The insurance carrier was accepted by all my doctors and was not one of the insurance companies known by doctors as no-pay or slow-pay.
Once you reach a decision, ask to be put on the Do Not Contact list to help slow down the calls. Your agent will call you, but it will stop the endless followup from other call centers.