Installed a Magnum system in my coach about 5 years ago and been working fine since. We have an Onan Quiet Diesel and a Magnum inverter which was already prewired so it made the install easy. You can set the AGS to turn on at a specific low battery voltage, and/or with a certain inside temperature. Both have been helpful for me. We did the install for our winter stay in Quartzsite and it was perfect. The temperature function protected our pups with A/C control, and the voltage control kept our batteries charged throughout the day.