As a Retired commercial truck driver, I love 7 wire. Its expensive but it keeps all the wires together in one package and if you are out on the road and need a replacement. Any truck stop has it on hand.
My comanche wire all go into a junction box. With ring connection. Water, mud, rodents resistant. Then it goes to a 7 wire RV plug. Then if needed I have an adapter to 6/4 plug.
My trailer has a junction box too. Easy to replace the lead to the trailer if ground down from dragging. Also its easier to chase shorts. Picture coming soon.