Just saw this,
I have been meaning to post about Comet and vitamin Q silver PIO caps.
I replace them in my line stage coupling position (comet), and output (comet /vitaminQ paralleled. Preamp is a very nice Jadis jp200 mc .. This swap was not cheap as the amp uses .47 uf and 1 uf in the positions.
The results were worth it though,.. these jupiter caps are the only ones I have ever tried that have this level of resolution , yet still retain a completely natural presentation. They are more natural sounding to me than duelund ( which I like their copper cast).