RE: If you had the choice, 10SXII or 9CAF ?
The 10SXII was a great radio; I flew one for years. Unfortunately, while its menu (and capabilities) is very similar to the 10X, it apparently doesn't use the same parts. Also, be aware that the PCM-10 series radios are type-specific; heli or fixed wing. You can do just about any plank-related programming you want with the heli version, but doing heli programming with the plank version is...interesting. I only mention that in case you are considering doing both
If you will do a search, you will run across threads asking a similar question to yours, in which I told of why I no longer use a 10SXII. Basically, if something goes wrong with it, you're probably SOL. The radio has been out of print for a few years now.
For that reason, I would say get the 9C. The 10SXII is more capable, but that won't do you any good if a chip or board pukes and Horizon doesn't have the necessary parts.