I was worried because my 2nd-hand 2014 RP-178 wouldn't lock up (skid) the trailer brakes at 20 MPH whenever I would try to adjust my integral GMC Sierra brake controller like the GMC book advised.
I think that a lot of the aftermarket controllers advise the same (skidding) procedure for adjusting the controller.
I suspected that the reason the RPOD wouldn't skid was perhaps that the RPOD brakes were not self-adjusting and needed adjustment (which brought me to this forum).
I didn't inherit any literature from Forest River about the brakes, so I got the Dexter Axle serial number from the sticker on the axle and called Dexter's service contact number. They told me that my axle has Forward-Self-Adjusting brakes which automatically adjust for brake lining wear (without braking in reverse). (Coincidentally, the initials "FSA" were also typed on the axle sticker)
Furthermore, they said that the brakes are designed not to skid and that Dexter wishes that the brake controller manufacturers would stop advising the 20 MPH skid procedure for brake controller adjustment.
It sounds like you are left to your own devices find a comfortable brake controller setting with these kind of brakes. I have been setting my GMC controler at 6.0 (out of 10) and it seems to brake the trailer OK. But to be honest, I can't sense much difference when I vary the setting.
I have made a habit of comparing (by feel) the temperature of my trailer brakes to my tow vehicle brakes. If the trailer brakes are hotter than the truck's, then I start backing-off the controller setting number until they both warm-up to about the same temperature. This is the best subjective measure that I've come up with to adjust my brake controller. I'm thinking of buying a temperature sensing gun to keep my hands clean and be a little more methodical/scientific.