A little late weighing in here, but, I started out running ds811's all around. First the rudder started fluttering around nutral when you flicked the stick... kind of the crazy violent shaking thing. I put a hs 5925mg to take care of that. Then towards the end of that same season the elevators started doing the same thing. From advise from people on rcu and horizon.. I ignored the fact that they were doing that b/c they said, "that is just something digital servos do". I was new to the hobby and did not know better. I was flying a slow flyby and saw my right elevator shaking in crazy flutter almost full travel both direactions. I was able to slow it down and get it to the ground. I put some hs 645mg and never had that problem again on the elevator, but, they were kind of slow and made it hard to hover.. later upgraded these to 5945's. Then the ailerons started just barely shaking as the others started out doing. That was ok though b/c I crashed this plane before those ever started to really have problems.. ha. Put hs 645mg's on the ailerons on ucd2 and never had a problem there.

I sent in the 811's and they switched out the gears for free and I used them on a twist for a while. Seemed to be great for that application. No twist anymore, but, I use them for throttle servos.. I like them there. Never really cared for the 537's on the throttle.

I am not the only person with this problem. There are other people and some who lost their plane (do a search).. usually you see it first with the big rudders where there is more torque and then it moves to other surfaces as things wear out. I don't get to fly very often so I would expect someone who flies a lot to run into the problem within a month on the rudder and about 2 months max on the elevators.