My wife has fallen in love with the Atomic SSI inflator/second. It's the feel of the inflator that really has her hooked. With it comes the integrated second and for the sake of service Atomic on the primary side would be the obvious choice for service and optimum compatiability. The budget would suggest the Z1 model.
The Z1 is not a cold water unit out of the box but does have an enviornmental kit option. Has anyone used these as cold water regulators? We'll surely be well down into the 40sF and 30s are likely at some point.