I can't comment on the differences between V-caps and other caps, because Paul Birkeland built each of my BH Customs pieces(phono, line, & poweramp) with V-caps from the get go.
However, Doc and I compared my linestage with the BeePre/BeeQuiet at BHeadquarters and found it was pretty close. Each piece had its strengths. My feeling is that circuit and tubes are critical, and parts come in second as determinants of sound. One day, perhaps I will have Paul build me a BeePre with boutique parts with the proceeds from my linestage; but for now I will not part with what I have, as it makes wonderful music with the Orcas+Subs.
Cheers, Hank