You know, that's not cheap, it works so they do it. There are other methods, of course, but that works. I usually reserve that method (chunk of brass.. ez connector..) for the throttle only. I would hate for that thing to come undone during flight if used on the elevator.. not good!!! So, I use clevis's and other methods of keeping the linkage on the servo arms and the control horns. On the clevis, I put a short lengh of fuel tubing over the clevis to keep it from opening, even after it snaps shut.

Like Justin Wilson, the cajun cook, says, both belts AND suspenders..

CGr.