I played Witcher 3 on Switch and it was ok. I’d prefer a better device but I was recovering from a surgery and it was great having the Witcher 3 on a handheld.
I bought Witcher 3 on PS4 and Switch but I exclusively play on the latter device. Sure, it looks like someone smeared vaseline on my screen, especially in hand-held mode. but it's still surprisingly pretty in its art direction and the story-telling is unaffected by the graphics.
It was perfectly playable.