I'm going to have a old 1962 Chrysler Mopar 318 fully rebuilt and maranised, closed cooling. for a classic wooden boat i've had restored.

The engine builder has offered to run stainless steel hard line plumbing, "aero style" fittings and braided hose or just regular plumbing.

Can anyone tell me the advantages/disadvantages of the various options?

I'm tempted to go for the SS hard line for aestetic reasons.

SS hardline takes skill, that's why it costs so much.
But nothing looks cleaner / classier imho

I prefer aeropquip hoses although they are not really USCG approved, Smitty