I have the synergistic blues fuses and are very good ,in my preamp section I tried the orange a 3-4% better then the blue but.currently $70 more per fuse and I needed 5 ,solution
i use Furutech nano fluid which uses nano particles of silver,gold i use a small foam swab and coated the fuse holder contacts good which contacts are crap and this alone gave a noticable boost in detail
it takes a few weeks to dry but gets better over the few weeks
others I know that have used it agree, even on power cords ,both sides .on ebay I get it straight from Japan for $120 delivered vs $170 here and it goes a long way and BTW synergistic uses brass
nickel end caps ,Hifi tuning use silver,gold.it says right on the synergistic site ,it not the best conductors ,vs silver,gold
that’s why the Furutech nano fluid makes a noticable enhancement it goes into the pours of the fuse,and holder.and save $$