The SeeLevel set-up on this truck and on my last truck have worked very well for us.
It's an easy swap if you can get to the wires and the tanks.
Read about them on-line and give them a call. They were very helpfull in my first retrofit a few years back. I specified them on my second build and they were again helpfull and easy to work with.
Now the builder of my coach uses them quite often for other customers.
PS After looking at your website you almost have to go with SeeLevel...