You will find, I am sure, a raft of opinions stated here on the group.Some like Tekosha, others swear by Prodigy and I use (and like) a Hensley Tru-Control.
Probably the most sophisticated controller is one which taps into the TV brake line and interprets the pressure signal received to control the electric current to the trailer brakes. It is expensive and I haven't heard many reports on how well it works.
Most (ALL?) other controllers use some type of accelerometer to determine that the driver is in the process of slowing down and use that signal as an input to a controller (computer chip) programmed with various parameters such as vehicle weight, trailer weight, etc and output the result to energize the electric brakes on the trailer.
Every engineer has his/her own idea of the proper algorithm to use in controlling the brake signal and programs the controller chip in accordance with that idea.
In theory they should all work equally well, but we know Murphey's law always shows up. In fact a combination of a specific truck/trailer/controller may work just great (like my Dodge 3500/Cougar 318/Hensley Tru-Control) whereas another combination may not work as well. That, I suspect, is at the root of all the almost religious embrace of a particular controller by some.
Also important is the fact that changing road conditions (snow,rain,gravel) will have a big effect on how the controller responds.
In the end, if what you have works, stick with it.
IMHO,
John