Have to agree it's only when runs (dep[ending on cable) need XLR to stop distortion (that why phone company used them before fibre optic era).But you'll here debate on it.I am a cable skeptic so a I have to hear differences.Rule of thumb is half meter will "sound better" but often times it means keeping the heat producing (or EFI distortion) from boards and especially power supplies being to close.If cost considerations enter into choice than the vcables probably cost too much.What for Me was interesting read where Mappleshade cables talked about keeping IC's short but keeping speaker cables long.Have enough cable length to give equipment room to breathe and reduce distoprtion in terms of spacing at minimum.But difference your talking about would be negligible.
Chazz
Chazz