I used to have 9-meter (27+ foot) Cardas Golden Ref speaker cables on my
VSR VR7 HSEs. They were great--smooth and balanced with a Pass X350 amp. I sold the VSRs because the bass was too strong for my room, but that was not because of the cables. The long Cardas GRs also served me well with Aerial 10Ts (very natural mids and highs). I still have them with my Harbeth SHL5s, and they are fine.
VSR VR7 HSEs. They were great--smooth and balanced with a Pass X350 amp. I sold the VSRs because the bass was too strong for my room, but that was not because of the cables. The long Cardas GRs also served me well with Aerial 10Ts (very natural mids and highs). I still have them with my Harbeth SHL5s, and they are fine.