Has anyone else had any (good) luck with MultiStar 20a ESC's?  I have been working on trying to defibulate a deadcat with 4 MS 20a's on it.  I had it flying pretty good, but the motors would not sound right... even when I calibrated the esc's in cleanflight they would not run at a constant rpm.  Running on the bench using cleanflight to spool up the motors, or even one at a time, they just did not perform right.

Flying the deadcat in acro seemed ok, the test flights were not much more than a hover.  Pitch seemed solid, roll was OK, but yaw it even a little and it would wobble and almost fall out of the sky.  I would like to fix this, but I fear its going to require replacing the JUNK 20a OPTO with some hardware that actually performs.

Since the first flights, I have re-flashed the ESC's  and now they are unresponsive.  I can flash them and they communicate with KK multicopter flash tool, but that is it.  Put them on the machine and try to run them an I get nothing but crickets.  

Any idea what to do?  At this point, I feel like taking a hammer to them and fixing them right.