Floored,

You didn't tell us what kind of servos or hardware you are using.

I had FMA coreless servos in my Dust when I first started out with the Jett FIRE 50. Things went fine for a while and then flutter started. Turned out I could wobble the servo arms back and forth almost an eighth of an inch even with the power on! The servos and/or bearings just gave out. After that I decided I'd never go back to cheap or "second tier" servos. I put a pair of JR 8101's in my Dust and the problem went away.

Nowadays I only use good JR or Futaba coreless servos in my airplanes. Dust designer Jeff Gilbert is a big fan of JR 4735's, something to keep in mind.

I am assuming you did a nice tight covering job with UltraCoat and have the pushrod guides installed.

Based on the experience I've had with my Dust I believe if you've got good servos and good hardware with no slop you should be free of flutter.