This is a bit of a hard choice for me. I have both a PS4 and a Nintendo Switch.
On one hand, if I got the PS4 version then I'd have all the console games so far available to play on my tv, though I'm not sure how different the controls would be on the PS4 version compared to the Switch version.
On the other hand, with the Switch version, I could play it wherever I want to, plus with playing both Theatrhythm Final Fantasy and TFF Curtain Call on my Nintendo 3DS, I kinda feel that I'd have a better/easier time playing a KH rhythm game on a handheld console.
Edit: I got it for the Nintendo Switch for Christmas, and I LOVE IT! ?