I have an EV5 from Dreamworks in my Hawk. If you want door sequencing and proportional brakes with two air bottles and digital readouts it is a handy device. On my Electra and UF I use the Robart one. it is an excellent unit in my opinion. There is an optional digital readout for it but you can count its flashes to tell you the psi. That one drives a servo to operate an air valve and in both cases I also use the same servo for brakes. I have no idea if they are the "best" but they both work.