Everybody who ventures to sea in a yacht must be able to assess the risks, probability and consequences, and mitigate them to a level that they can manage with confidence. As a person with a past search and rescue background, I say you should not go out if your expectation is that someone will come rescue you if you can't handle it. Yes extreme circumstances can overwhelm the best prepared sailor, but the vast majority of SARs are for people who should not be out there.
Insurance is only worthwhile if the claim gets paid. Having spent some time consulting in the industry, cheaper premiums correlate with less claim payments. Yep, get the best deal you can, but buyer beware. I went with the company with the best payment history, not always the cheapest.