John,

 

I've got an ES with every antenna buried.  I will likely relocate my transponder antenna to the belly at my next condition inspection.  I've had a few instances where ATC had trouble picking up my transponder.  Otherwise, my internal antennas seem to work fine.

 

An interesting observation, Kirk Hammersmith has an ES with all external antennas.  He's in the avionics business!  Maybe he knows something we done know.

 

Mike Easley

Colorado Springs