Im brand new to all this tricopter business but not new to the hobby. I am currently using that very same servo you linked and there are some things about it that forced a change of plans if you were planning on using it as per Davids original setup. In his setup there was a need to elevate the servo by placing a 1mm shim between the servo and boom. Doing this aligned the servo to the servo horn on the motor mount. With the servo in question and the one Im using, the motor mount needed to be elevated AND the servo wires moved around the corner so it will sit flat on the boom. Neither problem was much of a challenge to solve, padded up the motor mount site with wood from a craft stick, about a 1/16 inch. My motor mount situation forced me to add to either side of the boom to make a mounting surface onto which I screwed down the Flitest landing gear hinge. The servo wire issue was as simple as removing the screws from the cover and then using a razor knife to carefully cut a notch for the wires to relocate to just around the corner. Electrical tape the hole which remains.
The servo I used I mounted with zipties like everyone else but instead of cutting off the mounting lip all the way I just trimmed it down to about half its length and then used a razor knife to score and cut a slot along the top of the wood boom into which the remaining mounting horn locks into place. The slot I made I carefully cut and fitted the horn into so it took some pressure and compressed a bit of wood fiber. This little extra step makes the servo absolutely motion free even before the "sip-ties" go on. I also used some craft sticks to widen the boom where the zips hold things to the boom. Without them the ties never really got tight and nothing in the corner to bite into.
As for the servo, its cheap. I see a bit of twitch from time to time when in the air. Not sure if that is good or bad but it looks like the mount is sloppy and the absolute only slop detectable is inside that cheap servo. Given the extra measures I had to take to simply utilize that servo and making alterations where it cant be returned anyway Id buy something else.
EDIT: My first post! Glad to be part of the group!
