Truck built in trailer brake controllers

For years there were brake controllers made that sensed the brake fluid pressure to determine the brake current. This is the same technology used by the factory controllers now. Performance of these controllers was on par with the factory controllers offered today. Problem is that people didn't understand the superior performance and opted for cheap. All these years they could have had better and safer brakes. Since sales were weak, both BrakeSmart and MaxBrake went out of business. Only now are you seeing reports of how great the "new" controllers are compared to the after-market stuff made today.