Hi,
I think there are a bit of confusion here. I think it is possible that some of you have not owned a Skymaster landing gear designed by Likai. First of all, the hydraulic system you are referring too is the system with hydraulic pump. Skymaster have never used this system in any of their jets.
Skymaster have used an air driven oil fluid system - F104, with great success. I own one and have never had a leak or failure. This design was a 1st for RC. The second system we are talking about is the steering. It is closed loop oil system with a piston at top and piston at bottom. Servo move the piston and another piston move the steering pin. Also a first for RC and is used in Skymaster A4 with great success. I own one and would know. The reason we use this system is that there is no space for the servo to keep the system as close to scale as possible. Steering is smooth and a bump on the nose leg will not break a servo gear or link as the oil will take the load. These two designs will be followed by another fist for RC soon to be released....
Regards