I have used both and prefer the JR 9000 series. They just feel better to me. I will say that hitec customer service is the best...when I first started off with a revo, I burned up about 4-5 hitec servos and they replaced every single one of them for free (they even had a note on one of them saying something to the effect that the servo had been underwater
, but they would cover it this time!). You cannot beat their customer service. I do not know about JR (as I have not burned one out yet (more then 10 gallons on a 9000S and a 9000T so far). Really, you cannot go wrong with either one...