Hi Jim,

For whatever this is worth, I've been flying my electric Impact for about 5 months now and have not experienced any fluttering problem with the original stock setup. I don't know if there is anyone out there that has experienced a flutter problem with an electric Impact, but I would expect that the chances of this happening are a lot less than with a glow setup, due to less vibration through the fuselage, and slower cruising speeds.
I have been contemplating adding a horizontal piece similar to the radio equipment tray to the tail for additional stiffness.