I've never met or heard from anyone with a Brakesmart controller and would like to get some first hand feedback. The Prodigy has nearly all the same features as a Brakesmart but does not use/require that a sensor be added to the tow vehicle master cylinder, which makes installation easier. But I can see where Brakesmart could get some (small?) advantage by immediately knowing the TV brake output rather than waiting for an accelerometer to sense and kick in. Whether it is worth the price and install effort is another issue. But I & many others know a Prodigy works smoothly and efficiently.
Most of Brakesmart's claims are relevant to only to competitive low end controllers. High end controllers like the Prodigy and Primus have the same capabilities.
It is true that you do want proportional braking and you don't want pendulum-based technology (which is old stuff these days), but several controllers offer those advantages now. Avoid controllers that modulate braking by increasing brake pressure over time, i.e. the longer the brake pedal is down, the stronger the trailer brakes are applied. This has undesirable results in traffic or slight downgrades and other scenarios requiring light braking. The older Reese/Drawtites did this. They claim the newer Digitrac models have solved this problem, but I don't have any first hand experience to evaluate how well it works.