I got my specs from towerhobbies: 33 oz-in for S148 vs. 44.3 oz-in for S3003, both 4.8V. If S3003/3001 can't stand up to vibrations of helicopters, can they stand up to vibrations in Funfly-type plane with a 26cc gasoline engine? Standard size economy servo for general applications. Ideal for use with cars, power boats, yachts, electric and engine powered aircraft and helicopters. Most accurate servo specifications known are provided by ServoCity who measure servo data separately to that provided by manufacturer and in this instance Futaba servo specifications ServoCity agree with values provided by manufacturer. i.e. S148, S3003,3001,3004 are the same, only the assembly method and reliability, is of significant difference.