I certainly have enjoyed my DC meter setup to monitor my simple two zone switchable battery bank...

When camping off the power grid it is imperative to keep tabs on battery consumption.   Almost all of the places we go to here on the East side of the US has generator run time restrictions in place so we have to watch things pretty close to stretch it out until 8AM each morning when we can run our generator for three hours to re-charge everything back up again. 
I can watch both battery banks DC level and when they approach the 12.0VDC point I know it is time to start re-charging batteries.
My DC CURRENT meter monitors both battery drain current and battery charge current by observing the + or - symbol on the meter panel.  I can monitor up to 70AMPS DC...
My meter panel is mounted next to my entrance door of my OFF-ROAD POPUP so its in a good spot to observe the meter when I am inside of just outside the door.  It also turned out to very bright so I had to install meter panel ON-OFF switches.

This is my current battery setup layout...

My trailer is a 2008 model with low maintenance and all still working great - no need to upgrade for us...  My off-road POPUP will follow my 4WD Truck anywhere it will go...
  
Roy Ken