I put a hard wired PI unit in my trailer this season and am happy with it. Their customer support and service is also excellent, which really adds to the quality of a product.
Mine is a 30amp unit, and I have loaded up the electrical draw while plugged into a 30amp circuit. It has displayed current draws of 34amps before, so I'm not sure if that's actually true or if the read out isn't totally accurate...
2013 F-150 EcoBoost MaxTow
2013 Jay Flight 28BHS Elite
"My wheel lugs require more torque than your Honda makes!"