Bought eight of these when they were on sale. (They're identical to the servo's that Airfield uses on their EDF's) Installed four of them in my Great Planes Mini Super Stearman. Output gear stripped on the rudder servo with light use. Replaced with an HS55 and no more problems. Had another one of these installed on a flap and it flaked out after light use. Had to replace it too. Have had better luck with HS55's.