Fyi, might be getting brown outs from the bec if you are using the built in bec on the fusion se (i don't see an external bec in the pictures). Fusion se lists a 4amp bec and that servo can draw almost 7amps under load at 7.4v.Probably not buying a shift rc servo again. This thing is finicky, randomly locks for split second then pops back straight.
Fyi, might be getting brown outs from the bec if you are using the built in bec on the fusion se (i don't see an external bec in the pictures). Fusion se lists a 4amp bec and that servo can draw almost 7amps under load at 7.4v.