Chino,

What transmitter and receiver are You using?
If You have a rather new Futaba system that can take advantage of digital, and even brushless type servos if you prefer, that would be a good alternative. I have a handful of Futaba BLS153 servosand they are fine, lightweight, enough tourqe, can be used in both 4.8 and 6 volt receiver systems, are digital and brushless with metal gear. That is an example of Futabatop of the scale servosbut it is of course not needed in a classic pattern plane to have digital and brushless servos, metal gear etc. Since I have a Futaba TX and RX that can take full advantage of such digital brushless servo I tried so far the BLS153. So far so good. I use LiPo reveiver battery by the way with a PowerSystem electronic DigiSwitch as voltage regulator, voltage indicator and also to get rid of mechanical on/off switch.
Ball bearing servo is a good thing to have so check Futaba servo that has that and brusless motor (lastabout 5 times longer then brushed)is also good to have,metal gear is of course also nice to have and if you want digital servo (but they are more current hungry) to get better precisionyou can add that to the whishlist. Futaba S3050 has ball bearing, metal gear and is digital and is resonably priced (around $ 44 or so) and have good torque (72 oz-in 4.8V, 90 oz-in 6V) and reasonable weight (1.7 oz, 49 gram). If You have a Futaba radio with HS (High Speed) receiver you can take full advantage of digital servo to get even better frame rate (7 ms instead of 14 ms).So You have some alternatives to choose from, check Futaba US homepage servo section to read more if you need.

/Bo

PS. Back in 1970th I had an EK Logictrol super pro 7 ch (AM, 27 MHz) that had rather small red SM3P "Super-Mini" servo (no metal gear, no brushless etc of course) and they had a torqe of 28 ounce per inch (2000 gram per centimeter)and weight of 1.2 oz, 34 gram. I used these servos in both a Mach 1 and a Curare and they worked just fine (had Rossi 60 and 61 side and rear exhaust with pipe and retracts where I used a Futaba FP-S8, 8 kg/cm,high torque landing gearservo). The servos strangely enough never failed but I was extremely careful to mount them soft so vibration would not kill them. I still have the radio (but dare not to use it today in any airplane in the hostile 27 MHz band we have now with all the toys using 27 Mhz).