castle question:
md is a runaway state.
va is too, BUT
it's a commonwealth state, which in effect means you can't predict what will happen from one court case to the next. more based on case law and human experience.
the nice DA's (actually called CA's here in virginia - commonwealth's attorney) in Fairfax Co, Loudon Co, and Prince William Co, will pretty much give you a high five for blowing away a bad guy and move on. Arlington County and Alexandria County will be confused as to why you'd want to hurt anyone who entered your house, cause they would never do anything like that, especially since it could be the gradener or the au pair... they'll lock you up for being a gun owner if only the state would let them.
this, according to 25 year existence in this state, and recent discussions with several higher-up LEOs in prince william, loudon, and fairfax counties.