Accretion efficiencies (labelled with coloured dots) for two different DM core compacities (i.e. different m) with the same core mass of M_c = 10⁷ M_⊙ (RAR solutions A₂ and B₂). For comparison, the case of a Schwarzschild BH with a mass equal to M_c is also shown. Interestingly, solution B₂ reaches an accretion efficiency of 14%, which is considerably larger than that of the Schwarzschild BH.