Motor Driver Recommendations / Speed Controller for my Project

*Id like to control the brushed dc motor in my model train but I cant decide what motor driver to use

*I know that the motor in the model pull 4.5-5a with significant loading at 20v (max voltage/full speed)

*Earlier I was looking at motor drivers like this planning on running 2 units (4 bridges) in parallel for a theoretical 8a continuous

*After some research I read the ic's in a module like this were inefficient, I guess the voltage sags a lot under load

*So that brings me to motor drivers like this that use "power" mosfets and have lower resistance (im certainly not an expert)

*I have even considered using a brushed rc car speed control but I cant find one I know will work at 20v and not be overkill in the amp department

*So please give me your recommendations, Thanks!