Just an fyi guys. If you have a wheel speed sensor go out, an abs light come on or a traction control issue, your GM oem controller will flash on your dic that you need to service the trailer brake system also (possibly disabling the system). While chances of these failures while towing are slim, it would suck.
I just hate that the systems are tied together, after working on them (oe systems)and having always used hoppy controllers for trailer braking, I could go either way on it. 6 of one, half a dozen of another.