T&T: Xantrex Link-20 battery monitor (or equivalent product)

[Pete Balkus]

I was wondering if anyone has experience installing and using a Xantrex
Link-20 battery monitor (or equivalent product) to monitor two banks of
batteries (house & start).

Per the MFG write-up:

    The Link 20 provides complete battery status information for two battery
banks, 
    respectively. Simple and easy-to-use multicolor displays show volts,
amps,
    amp hours consumed, and operating time remaining. 

    The Link 20 allow you to select Automatic, Sleep and Scanning modes and 
    automatically calculate and display charging efficiency. The Link 20 can

    monitor a house bank and starting bank or two house bank batteries 
    at the same time. 

Questions:

   -  How much more useful is it to have the ability to display 
      "amp hours consumed" when anchoring, etc, vs just referring 
       to battery voltage?

    - How difficult is it to install?

    - Given cost - is this a worth while addition?

Thoughts, feedback and recommendations appreciated...


      Pete