do cartridge lead composition make a difference?

Dear Lleall: IMHO yes it makes a difference for the better or worse depends what the choice. IMHO does not depends on synergy not only with the cartridge but with any thing else.

I think you must choose the best alternative that can degrade the less the cartridge delicate signal.

A good silver wires are IMHO the way to go but not only looking for the silver wire it self but for the female wire connectors that always makes a difference too and as with the lead wires silver is the way to go.

Regrads and enjoy the music,
R.

Thanks, Raul, for taking the time to answer.
Much appreciated.
Sincerely,
Lea

Do they make a difference?

Yes

Does it depend on synergy with the cartridge?

No