One question Bro Boss.. u are talking about EP or GP buggy ?? infact, i dont really recommend 9550, since its a low profile servo with pretty low torgue which cannot handle buggy torgue eating requirements.. I would suggest those with metal gears with at least 8kg output torgue for EP buggies ( just my opinion ) if u r talking about GP buggies.. required alot more than that
Look at its spec ..
Dimension 40.5 mm x 21 mm x 25.4 mm
Weight 45 g
Operating Speed 0.11 sec/60°
Output torque 6 kg-cm
Coreless motor, 6.0V only
Dimension 40.0 mm x 20.0 mm x 36.6 mm
Weight 56 g
Operating Speed 0.10 sec/60°
Output torque 8.7 kg-cm
S3003 Analog servo
4.8V or 6.0V
Dimension 40.4 mm x 19.8 mm x 36.0 mm
Weight 37.2 g
Operating Speed 0.23 sec/60° (4.8V)
0.19 sec/60° (6.0V)
Output torque 3.2 kg-cm (4.8V)
4.1 kg-cm (6.0V)