If you have "DELAY" in your braking with disk brakes you most likely have air in the brake lines!!! My RV and Boat Trailer both have the same HydraStar actuator the biggest they make, neither have any delay.
With a good brake controller that is set properly the braking experience should be nearly seamless. There is virtually no pressure building as the lines are full. If they are not full as in air in system, YES there will be "delay".
I had this delay issue rite from the factory. It's a simple job to bleed the brakes as it can be done by one person. Better with two as the revisor is not large on these pumps and you don't want to get low on fluid as then you will have more air in the system. I asked a fellow DRV friend about checking his actuator for fluid and he gave me a blank stare. Frequent checking and topping off is an item to have on the maintenance list.