[jw]

Having just have to replace the 1/0 welding cable, that was my battery cable, as suggested by the marine surveyor for a insurance valuation, in my Hatteras with marine grade wire, I would suggest that after all the time and money spent on these boats why put the cheap wire back in?
The marine grade wire insulation is thicker and will withstand the water and salt much better.
I personally use all marine grade wire, with the heat shrink terminal end and put dielectric grease on anything exposed, terminal blocks, ring fittings, etc.
As my daddy used to say, There are no mechanics offshore when she breaks.
22cents worth.