I have both the 10X and 9303 and use them extensively. I prefer the 9303 because of it's simplicity in setting up the controls but go to the 10x when I need the extra channel. As mentioned you can buddy box them but you can't auto transfer settings from one to the other. I also have the synthesized RF module and can switch it back and forth between the two. My friend has the 9C and has no problems with it. I suppose it comes down to what you want and how much money you want to spend.
booker