Mit Spectral câbles with non spectral amp.

I should want to know if some of you have experienced using spectral cable on non spectral amp. I want to use a RCA interconnect in place of my MIT proline twin 350 terminator as my valve pre works better on RCA output. Spectral 350  ultralinear II are far cheaper as MIT 350 in europ and I need minimum 17 feet.
Thanks.