Interconnects for Musical Fidelity

I thought I'd address this question more specifically this time. I recently bought the MF Tri-Vista 300 integrated, which I love and a used version of the Nu-Vista 3D CDP is on the way. I have no need yet for SACD, so the accompanying Tri-Vista SACD would be overkill for me right now. I think the synergy of the two machines will be great. Now comes the interconnect. I need some advice from you fine and knowledgeable audiogoners. Which would you recommend with this system? I also recently won the Antique Sound Labs MG HEAD DT OTL MKIII Headphone amp to hook into this system to go with my Sennheiser 600's. I'm going to need an interconnect from the CDP into the headphone amp and another from the headphone amp into the Tri-Vista. what would you recommend? If anyone knows, I'm also curious about the OTL/Transformer function on the headphone amp. The manual doesn't state the purpose of this switch. Does anyone know? One of the advantages of the Tri-Vista as well as the other top-level integrated limited editions released by MF is the separate dedicated power supply box. I was curious and wrote previously about this and asked if it would ever be necessary, given the separate power supply box, to buy a better power cable. Would such a move be redundant and unhelpful or would it generate better sound? I also recently bought a separate multi-tap to run from my outlet to the electronics and it has remarkable improved the sound coming into the supply, so perhaps an additional power cable would be unnecessary. I don't know. Any recommendations on these questions would be greatly appreciated. Some have recommended the Harmonix interconnects. Few are selling on the Audiogon, though, and I prefer to buy used (none sold locally). Are there comparable interconnects from other brands? Nordost, Transparent, Kimber, or Tara Labs? How do the Red Dawns, SPMs and QF lines stack up with the Valhallas and Valkyrjas? Thanks.