How did you come to that conclusion? Not long ago, before digitals were around, this was the set up of choice for everything up to 30% planes with gassers. I personally had the exact same set up on a Byron 27% Sukhoi with a G-62 and they were plenty strong. Regardless of the type of flying you do, these servos will hold up. Remember, this is only a 90 size plane and the elevators on my Sukhoi were bigger than the rudder on the Yak. I saw one of these fly today with a Saito 180 and it was more than what was needed. Unless you've already got the 140, I'd recommend the 110, if you can find one.