This is your old servo specs
Modulation: Analog
Torque: 6.0V: 86.00 oz-in (6.19 kg-cm)
Speed: 6.0V: 0.20 sec/60°
Weight: 1.59 oz (45.0 g)
Dimensions:
Length:1.60 in (40.6 mm)
Width:0.80 in (20.3 mm)
Height:1.43 in (36.3 mm)
Motor Type: Brushed
Gear Type: Plastic
Rotation/Support: Bushing
This is your new servo specs
- Model: k2-3620
- Metal Casing. Protect the servo motor from overheating
- Torque(4.8V): 16.5 kg-cm (229.1 oz/in)
- Torque(6.6V): 20.0 kg-cm (277.7 oz/in)
- Speed: 0.18 sec (4.8V) ¦ 0.16 sec (6.6V)
- Operating Voltage:4.8 ~ 6.6 DC Volts
- Weight: 60 g (2.12 oz)/Servo Motor
- Bearing Type:Ball Bearing x 2
- Motor Type
C Motor
As you can see, your old servo, at 6 volts (4 AA batteries provide 6 volts. And yes, the new servo is saying 6.6 volts) you went from 86 oz/in of torque to 277 oz/in. A gain of 191 oz/in. You also went from a speed of 0.20 sec/60º to 0.16 sec/60º. So even if you compare the stock servo at 6 volts, and the new servo at 4.8 volts, you are still stronger and faster than the stock servo.
Again, those D-Bags like the one on the other forum is exactly why I created this site. I had the same experience on those sites when I first started getting into aircraft and I got tired of it very quickly. I never visit those sites anymore.