Depending on the controller, proportional controllers will give different numbers based on stopping need. Mine has some sort of inertia sensor and it applies more pressure based on how hard I'm stopping. Just follow the set-up instructions and give it a whirl. Mine took some adjustments to get it just right. Mine also has "boost" feature which allows me to set my trailer brakes stronger or weaker than those of my TV. You may need to dial in some boost.
Bryan, Pam and Cameron
2003 Jayflight 27BHS, 2004 Ford Expedition