I use these for boats: http://www2.towerhobbies.com/cgi-bin...?&I=LXFV40&P=7. They seem very secure and are actually easier to remove than a traditional ball joint. Some of them have survived heavy abuse, such as shearing off the servo output shaft, but keep working well. They also have a 2-56 version: http://www2.towerhobbies.com/cgi-bin...?&I=LXFV39&P=7 for lighter duty such as throttles.