Interesting perspective OP. I mounted my aftermarket brake controller on the right side of my 2004 Suburban and ran that way for 14 years. Having no knowledge of OEM placement in any vehicle, I purchased my 2017 GMC without a care as to the location of the brake controller. After having towed half a dozen times with the new truck, I have to say I love the location on the left. As for emergency braking, I have rarely had to mess with it, however, I always do a rolling manual brake check on the trailer when starting out. Left side still wins out for me for brake checks.
