Armored Heart Vertusent Music Group The Darling family they ain’t. Hailing from Mount Airy, N.C. (the real-life Mayberry of “The Andy Griffith Show”), the four members of Runaway City have committed themselves not to bluegrass but completely competent modern rock in the vein of Daughtry and Nickelback and Breaking Benjamin and just about every other grittily sung, guitar-driven song on…