Not all that many years ago a servo with 48 in. oz. was a pretty good servo and we used them on giant scale planes. Big stunt planes with large controls needed more power so two or more servos were used on one serface ganged together. Today we tend to go a bit over board on what is thought necessary for servo power. The new big digital servos are great but not always a must have item. I still use a lot of standard servos and on most planes that's all they need. Your servos are just fine for the use.