Post and crown or extraction and bridge?

63 year male, broken #13. Deep filling had decay and inner half broke off near bone level below gum. Dentists have said there is adequate structure remaining but needs to have gum cut away for P&C. Only 50% to 80% chance of long term success is offered for P&C, restoration may last "1 month to 15 years". Bridge life unknown. I know costs for extraction and bridge, a P&C crown, but not for post, root canal and associated work for P&C. How do I decide whether to keep to tooth or extract ?