Tdaudio, you are quite right, the 350.5 does offer about another 35 to 45 class A then the 250.5. What you are leaving out is that the first 5 to 8 watts in the 350.5 are single-ended class A, not just class A. For over nine years I powered my system with Aleph 1's untill I replaced them with an Edge NL-10. This was replaced by the Pass Labs X 350.5 because it gave me back the warmth/smoothness of my Aleph's along wonderful clarity, dynamics, and powerfull bass extentsion that the Alephs lacked. My hunch is, that you would love the 350.5 in your system.