Posted for "Mark & Lisa" <marknlisa@hometel.com>:

 Have you tried posting on the Aero-electric mail list?  Bob Nuckolls
 presides over the list; he has published a work called the Aeroelectric
 Connection and conducts seminars on electrical system design and
 construction.
 
 Check out http://www.aeroelectric.com to see Bob's website and order his
 book.
 
 Check out http://www.matronics.com to subscribe to the email list.
 
 The short answer to your question is stick with a 14 volt system unless you
 have special needs.  28 volt components are less available and consequently
 more expensive.  Some components aren't available with a 28 volt option --
 trim servos come to mind -- requiring the use of a step-down transformer to
 make 14 volts from 28 volts adding expense, complexity and inefficiency.
 
 The most-often quoted advantage to 28 volt systems is weight savings due to
 smaller AWG (American Wire Gage)wires.  In reality, the difference in wire
 size *might* save you 5 lbs -- at the expense of fewer options and a more
 costly system.  Subscribe to the email list and you'll have access to the
 archives.  A quick search of the Aero-electric list archives will turn up a
 wealth of info on this subject.
 
 Mark & Lisa Sletten
 Legacy FG N828LM
 http://www.legacyfgbuilder.com