I also have dedicated lines if it matters. I also used to own Alephs and can say with all certainty Aleph series equipment and X-Series Pass gear are VERY different. Having said that, I went through a few cables with the Pass X250 before settling on the Syn Research Des Ref Squared.
I used a BMI Eel and Whale, Syn Res's Master and Ref Standard, VdH's Gold, a Delta Labs Power cable, a PS Audio cable with a large conditioner on it, and a few others loaned to me by friends so they could try my cables on their systems. I can not say I have found the "ultimate combo" for an X250 yet, but of the ones I have tried, the Des Ref Squared mated best to my equipment.
I still own and use many of the cables above, just not on a critical piece of equipment. I use them on a Lexicon processor, DVD player, Theater amp or on my TV. They are all good enough for those items.
Best Regards, AaronM