It sounds strange to me.  I would expect an occurrence policy to cost more than a claims-made policy because the insurer is accepting liability for potential claims in perpetuity, so long as the search was performed during the policy period. 

Last I heard, insurers were dropping out of the E&O market.  It is surprising to me that an insurer would enter this market with lower rates and offer occurrence policies.  My advice would be to check with you state's department of insurance and make sure the insurer is authorized to sell such policies.  Check the companies financial rating with Fitch, Moody's, Standard & Poor, etc.  It might also be a good idea to have your attorney review the policy to make sure it provides the coverage you need.

Insurance is complicated and I would be wary of a cheap policy that seems to offer more coverage for less. 

Best,
Robert A. Franco
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