NHibernate and Linq

If the objective is RAD [rapid Application Development], Linq comes in handy.NHibernate, has very interesting support for the inhertance and the object can be stored as Table per Calss, Sub-Class or "Hierarchy", this evaluates to the ability to write flexible code and "Polymorphic Queries". It is possible to either write mapping in xml document or as strongly typed objects, this should be design descision based on what you would like to acheive w.r.t ability to Refactor, configure etc...