I sold both my Savox 1251's a long time ago when I got back into TC racing. Even had the race director commented how much more consistent I was when I swapped it out for a Futaba brushless servo. Thought it was an issue with the car but it was the Savox servo the whole time. It doesn't seem like it has the resolution of a higher end Futaba/KO despite otherwise good specs on paper.
My best servo now is my KO RSX one. Just picked up an Xpert brushless servo to try out.