I would ask them to remove that language.  If not, I would at least cross it off and initial it.  I have a standard "limit of liability statement" as part of the form that I return work to the client with.  It limits my liability to the cost of the search, regardless of E&O insurance.  If they accept the work and further use it downstream, it means they accept the terms as given.  I think this is only fair, since we as abstractors do not have any control of the work downstream of us.  If they make a mistake on the legal, leave out key parts, misstate a mortgage, etc.  How are we to know and how can we defend against that????  The limit of liability stops all that.  It has proven it's worth in gold a few times for me already...