Today I learned about Brass vs. Phosphor Bronze. There’s more to know. My guess is that Phosphor Bronze is probably best for Contact, Commercial MATE-N-LOK, Socket, Crimp, 18 AWG, Tin Plated Contacts.
Update: actually looks like tin plated brass is more common/standard/cheaper? than phosphor bronze. I think it’s a technical detail that probably doesn’t matter much. Some products just say “copper alloy”, and they’re both copper alloys.