old glass hull v. new glass hull
>>with the rebirth of sandwich core hulls
I''m not sure what rebirth you refer to. The big three sailboat manufacturers, Hunter, Catalina and Beneteau, have stayed with solid glass hulls. Given their expertise with cored construction in decks and the fact that cored laminate hulls could reduce their build costs (and boat weight), they must think all glass delivers benefits despite the cost (and weight).
Meanwhile over in the powerboat world where some volume builders have adopted cored hull construction, complaints and lawsuits about hull problems apparently abound. You heard it here, the class action lawsuit will show up soon...
I guess hull construction is one of the numerous choices we all make in deciding what boat is right for us, a buyer needs to understand the tradeoffs and then make an informed choice about the risks he/she is willing to take for what benefits..