I have individual battery disconnects for both the chassis and the house batteries. Both are installed on their respective battery ground terminals, rather than the positive.
Although there's no loss of data or settings anywhere due to disconnecting the house battery, when I disconnect the chassis battery I do lose the correct time on the vehicle clock display. All other data and settings, including odometer, maintenance information/intervals, radio presets, bluetooth settings, audio settings, GPS preferences, etc. are all retained.
Although I suspect more and more electronics use EEPROM storage rather than power-dependent RAM to store configuration information, not all vehicles and/or audio systems are created equal and your results may differ. Regardless, it is extremely doubtful that you'd lose any truly critical data, so until you give it a try, you're never going to know how much of a hassle it will be to reprogram your various systems.
