For my N Scale layout I used 14G Kitchen & Bath Romex.
It is very flexible & worked great for the buss on my layout.
I have 5 36x80 "Modules" plus a 60x24 bridge between them.
That's almost 40' of bench work.
I did have to run a jumper across the middle.
There was a noticeable loss of power furthest from the command station.
But now it works fine.