There are 2 adjustments, one is for how agressively they grab when you press the brakes the other is for how much pressure you apply. The aggressiveness is usually a slider and the pressure is a wheel. Set the aggressiveness for the max so it grabs as much as possible right away and set the pressure to a comfortable level and then everytime you press the pedal it will go right to that setting.

 

my prodigy is solid state. you have to get it set first (just before wheel lock) then you can use different brake settings etc. works pretty good

 

I use the Prodigy also. I've read that one of it's additional features that other brands do not have is it can control up to three axles. Not sure of your requirements, but I haven't had a bit of trouble with mine.
If you get a controller installed and want to go another step further, consider a exhaust brake. I know it's more money to throw at the truck, but they work great. I have a Pacbrake and it definately slows the load down without ever even touching your brake pedal. Besides that, I love to mess with people that are next to me with their windows down. I let off on the accelerator and the engine goes to sort of farting and the look I get from those gassers is priceless !!!!!!!!!!!!