I use those type of plugs a good bit. I have heavy battery cables run from the front of the truck to the back, then I can plug in a receiver mounted winch in the back of the truck (same with my Jeep.) I have a short length of cable attached to the trailer battery and then I made a short jumper so I can connect the trailer battery to the truck while in motion (or stationary) to charge the trailer battery with the truck's alternator. They work well, an occasional coating of contact grease keeps the corrosion at bay. I love the solid electrical connection they provide.
2015 XLR Hyperlite 30HFS5 (mods being performed regularly)
2009 Salem LA 292fkds (gone)
Nights- ('12)23 ('13)23 ('14)15 ('15)31 ('16)25
2014 Harley Davidson FLHX (XLR cargo)
2014 VW Jetta TDI (diesel sipper, camping support vehicle)
2011 Ram 2500 CC 4X4 CTD, B&W Companion (toy hauler hauler)