2721 vs. 4721 Servo
 

What benefits do I get (other then the metal gear) if I buy JR 2721 servos instead of 4721 ? Is it a more reliable servo ? Is it harder to strip ? In other words, is it worth paying more for this servo or should we just move up and get the 8411 ? Application would be for 3D type planes as well as 30% + planes.

2721 vs. 4721 Servo
 

It is harder to strip with the metal gears, and therefore better for giant scale planes. It is equally reliable overall. The question of if it is worth paying more for it depends on a lot of factors, but overall I would say it is better suited for those type of planes than the 4721. The 8411 may be an even better choice, but it may not be necessary.