The advantage to the choke servo is that it offers a "backup" kill system in the event of an emergency. Let's say for whatever reason, your throttle is stuck wide open while in the air[X(] An extra 2-3 oz is nothing to be concerned about. Not at all complicated. You do, of corse have the option of a fiber optic kill switch.
Really, I can't think of any reason NOT to use a servo.
1 Simple to set up
2 Convenient
3 Minimal weight
4 SAFETY, SAFETY, SAFETY.

Just my opinion. Merry Christmas.