I am using the DuelundHybridcopper silver they are Great and seamless it’s like having a small silver bypass it takes200 hours to settle in to 95%
on my preamp I have a 1 uf Jupiter Copperfoil ,and to open thetop up a bit a .022 vh audio Cutf tefloncopper foil2.2% of the 1 uf value after 3-400 hours sounds really good , theDuelund hybrids slightly better.