635's and 645's are way overkill.

Some have brought up that the Karbonite gears are fairly brittle and that the vibration from a solid throttle link will wear them out. They suggest the nylon gear servos, like the 3003's, can do a better job with vibration.

Others will point out that a servo with very little backlash and deadband are critical for repeatable idle settings.

Then there are the people who will invest big bucks in a throttle servo and install a sloppy linkage.

Here are the bullet points:
<ul>[*]You don't need a lot of torque. Cheap standard servos have plenty of torque.[*]Sloppy linkages negate your investment in expensive digital servos[*]Vibration is a factor to consider (I know plenty of people who have not had any problems with Karbonite geared servos). [*]If you want a dependable idle you want a servo with very little backlash and relatively little deadband (in other words, very repeatable positioning). But your financial investment must be matched, or exceeded, by your mechanical setup.[/list]Paul<br type="_moz"/>