Ni80 26/32 Clapton wire for me, although I might try SS yet. I was doing 3mm builds, but recently went to 2.5mm.
Not sure I'm seeing any major benefits or difference.
For MTL I use 28g Kanthal. I used to use 27g, but the spool ran out and I haven't bothered to replace it. I do find that Kanthal starts tasting metallic to me after a few dry burns. Haven't tried ni80 for MTL as I only have 22 & 24g.
