I have a .30 Nitro Shuttle Z /ZX that I've had for many years that flew on JR NES-401 servos a few times and then was put away. I want to start flying helis again and want to update my servos to something more appropriate in keeping with current technological advances. I already have a Futaba AVCS GY401 gyro with the S9253 servo that came with it. So next is the rest of the servos? Do I need digitals and metal gears, or is this overkill for a noob? I have a set of JR DS537 but I thought I heard somewhere that they are not suitable for helis? I fly JR FM/PCM gear. Anyone have any recommendations on a good value and bang for the buck on .30 size servos? I travel all over Asia and Europe, so it is easy for me to pick up import stuff (HK) as well as the more spendy high end stuff. I'm just rather overwhelmed by all the choices.

JR DS 811's, Hitec 635's, Align DS610

You dont need anything special.

The Shuttle Z/ZX does not have the collective range etc. to be an extreme 3D bird so for sport aerobatic flying, which would be the most demanding type of flying I would assume yuo will probably want to do with it,

The important thing therefore, is to insure you get dependable servos that can take the extra vibrations of a nitro heli over the long term, while remaining relatively precise, with adequate power. There are many such servos on the market that will do the job admirably without hitting the wallet very hard.

My favorite for 30 size helis are the Futaba S-3151 digitals - dependable and relatively low cost.

Yup, I forgot about the 3151's