Yeah, you are good to go. The only upgrade for you would be the CX. Here is a full comparison between the two models:
The CX supports 4k VRR at 120 Hz, while the C9 only supports 1080p VRR at 120 Hz (4k VRR at 60 Hz). Since there will be almost no games that run in 4k at 120 FPS, I don’t think you are missing much.